mathewhe/aqua_rat huggingface dataset:
Question: Three houses of the same type were advertised to be let in a locality. four men made separate applications for a house. What is the probability that each of them applied for the same house.
(A) 1/4
(B) 1/6
(C) 1/8
(D) 1/9
(E) 3/256
Rationale: Since each of the house has same probability of getting selected so for each men proability of selecting a house out of 3 houses 1/3
Let us consider case where all 4 men choose House no 1
So for First men it will be 1/4,second men 1/4 , third men also 1/4 and fourth man 1/4
So probability of selecting house no 1 is 1/4*1/4*1/4*1/4= 1/256
And since there are 3 such house so probability that each men select the same house is 3*1/256
Ans is E
Answer: (E) 3/256
Question: Tough and Tricky questions: Probability.
Medical analysts predict that one over five of all people who are infected by a certain biological agent could be expected to be killed for each day that passes during which they have not received an antidote. What fraction of a group of 1,000 people could be expected to be killed if infected and not treated for three full days?
(A) 16/81
(B) 8/27
(C) 2/3
(D) 19/27
(E) 61/125
Rationale: At the end of each day we will have 4/5 alive. So after 3 days we will have (4/5)^3 people alive. Therefore, fraction of dead people will be 1-(4/5)^3=61/125.
The correct answer is E.
Answer: (E) 61/125
Question: A welder received an order to make a 1 million liter cube-shaped tank. If he has only 2x3 meter sheets of metal that can be cut, how many metal sheets will be required for this order? (1 cubic meter = 1,000 liters)
(A) 92
(B) 90
(C) 82
(D) 78
(E) 100
Rationale: The question say:A welder received an order to make a 1 million liter cube-shaped tank. (1 cubic meter = 1,000 liters)
In other words, the tank is going to have a volume of 1000 cubic meters. That would equal 1 million liters.
A cube with a volume of 1000 cubic meters must be (10 meters) x (10 meters) x (10 meters).
The question doesn't specify whether this tank should have a closed top or an open top. (The real GMAT is good about specifying things like that.) Here, we are going to assume a closed top, only because if the top is open, we don't use enough metal --- we get an answer smaller than any of the answer choices. A closed-top cube, a full cube, has 6 sides, each of which is (10 meters) x (10 meters). That's a total surface area of 600 sq m.
The question tells us:he has only 2x3 meter sheets of metal that can be cut.
Each sheet has an area of 6 sq m. How many of these need to fill up 600 sq m? 600/6 = 100. He needs 100 sheets.
Answer =E
Answer: (E) 100
Question: If 8 < x < 9, and x^2 = (10 – y)(10 + y), which of the following is a possible value for y?
(A) –7
(B) –6
(C) 3
(D) 4
(E) 5
Rationale: Given : 8<x<9=> 64<x^2<81
Given X^2 = 100-y^2
Therefore 64<100-y^2<81
-36<-y^2<-19 = 19<y^2<36
Only (E) y=5 => Y^2 = 25 satisfies the above equation.
Answer: (E) 5
Question: If 2x + 3y = 26; 2y + z = 19 and x + 2z = 29, what is the value of x + y + z ?
(A) 18
(B) 32
(C) 26
(D) 22
(E) None of these
Rationale: On solving equation we get
x = 7, y = 4, z = 11
Answer D
Answer: (D) 22
Question: W=(429)^2 * 237 * (1243)^3 is thrice of ?
(A) 33605 * 31960 * (1243)^2
(B) 33654 * 538219 * (1243)^2
(C) 33891 * 533247 * (1243)^2
(D) 34122 * 532004 * (1243)^2
(E) 34606 * 534572 * (1243)^2
Rationale: W=(429)^2*237*(1243)^3 is an odd number.
Among answer choices only C is an odd number, (so thrice C also will be an odd number).
Answer: C.
Answer: (C) 33891 * 533247 * (1243)^2
Question: A train 125 m long passes a man, running at 5 km/hr in the same direction in which the train is going, in 10 sec. The speed of the train is?
(A) 40
(B) 50
(C) 60
(D) 70
(E) 80
Rationale: Speed of the train relative to man = 125/10 = 25/2 m/sec.
= 25/2 * 18/5 = 45 km/hr
Let the speed of the train be x km/hr. Then, relative speed = (x - 5) km/hr.
x - 5 = 45 => x = 50 km/hr.
Answer: Option B
Answer: (B) 50
Question: A bag contains 50 P, 25 P and 10 P coins in the ratio 5: 9: 4, amounting to Rs. 206. Find the number of coins of each type respectively.
(A) 200,360,160
(B) 200,350,150
(C) 190,400,500
(D) 190,290,390
(E) 200,300,400
Rationale: let ratio be x.
Hence no. of coins be 5x ,9x , 4x respectively
Now given total amount = Rs.206
(.50)(5x) + (.25)(9x) + (.10)(4x) = 206
we get x = 40
No. of 50p coins = 200
No. of 25p coins = 360
No. of 10p coins = 160
answer :A
Answer: (A) 200,360,160
Question: 1,5,13,25,__
(A) 26
(B) 30
(C) 31
(D) 41
(E) 43
Rationale: Series increased by
1
1 + (4*1) = 1 +4 =5
5 + (4*2) = 5 +8 =13
13+ (4*3) = 13+12=25
25+ (4*4) = 25+16=41
ANSWER:D
Answer: (D) 41
Question: The digital sum of a number is the sum of its digits. For how many of the positive integers 24-130 inclusive is the digital sum a multiple of 7?
(A) 7
(B) 8
(C) 14
(D) 16
(E) 20
Rationale: is there other way than just listing?
25
34
43
52
59
61
68
70
77
86
95
106
115
124
14 ways..
C
Answer: (C) 14
Question: At the wholesale store you can buy an 8-pack of hot dogs for $1.55, a 20-pack for $3.05, and a 300-pack for $22.95. What is the greatest number of hot dogs you can buy at this store with $200?
(A) 1,108
(B) 2,500
(C) 2,108
(D) 2,124
(E) 2,256
Rationale: We have $200 and we have to maximize the number of hot dogs that we can buy with this amount.
Let's try to find out what is the maximum number of hot dogs that we can buy for a lesser amount of money, which in this case is 300 for $22.95.
For the sake of calculation, let's take $23. 23x8 gives 184 ,i.e. a total of 300x8 = 2400 hot dogs . We are left with ~$16. Similarly, let's use $3 for calculation. We can buy 5 20-pack hot dogs (3x5), a total of 20x5 = 100 hot dogs. So we have 2500 hot dogs.
2108 looks far-fetched (since we are not likely to be left with > $1.55). Hence, (b) 2500 (ANSWER B)
Answer: (B) 2,500
Question: What will be the cost of building a fence around a square plot with area equal to 49 sq ft, if the price per foot of building the fence is Rs. 58?
(A) 3944
(B) 2287
(C) 1624
(D) 2668
(E) 1298
Rationale: Let the side of the square plot be a ft.
a2 = 49=> a = 7
Length of the fence = Perimeter of the plot = 4a = 28 ft.
Cost of building the fence = 28 * 58 = Rs. 1624.
Answer:C
Answer: (C) 1624
Question: A pump can fill a tank with water in 6 hours. Because of a leak, it took 7 hours to fill the tank. The leak can drain all the water in ?
(A) 15hr 10min
(B) 16hr 20min
(C) 17hr 30min
(D) 42hr
(E) 14hr 25min
Rationale: Work done by the leak in 1 hour = 1/6 - 1/7 = 1/42
Leak will empty the tank in 42 hrs
Answer is D
Answer: (D) 42hr
Question: The speed of a boat in still water is 60kmph and the speed of the current is 17kmph. Find the speed downstream and upstream?
(A) 77,43 kmph
(B) 80,80 kmph
(C) 80,42 kmph
(D) 80,40 kmph
(E) 83,40 kmph
Rationale: Speed downstream = 60 + 17 = 77 kmph
Speed upstream = 60 - 17 = 43 kmph.Answer:A
Answer: (A) 77,43 kmph
Question: If {x} is the product of all even integers from 1 to x inclusive, what is the greatest prime factor of {18} + {16}?
(A) 23
(B) 20
(C) 11
(D) 19
(E) 2
Rationale: Soln:
{18} + {16} = 18*{16} +{16} = 19*{16}
ANSWER:D
Answer: (D) 19
Question: A man can row with a speed of 15 kmph in still water. If the stream flows at 3 kmph, then the speed in downstream is?
(A) 33
(B) 77
(C) 20
(D) 18
(E) 71
Rationale: M = 15
S = 3
DS = 15 + 3 = 18
Answer: D
Answer: (D) 18
Question: Can you find the smallest non fractional number such that
If the number gets divided by 6 , we get the remainder of 1;
If the number gets divided by 7, we get the remainder of 2
If the number gets divided by 8 , we get the remainder of 3;
If the number gets divided by 9 , we get the remainder of 4.
(A) 1006
(B) 1230
(C) 1010
(D) 1200
(E) 1300
Rationale: A.1006
As we know LCM of the numbers 6 7 8 & 9 is 1008
So if i divide 1008 by any of the four number , it gives remainder as 0.
Now to get reminder as desired, is should be 2 short of 1006. (3-1,4-2,5-3,6-4 )
Ans:option A
Answer: (A) 1006
Question: A sum is invested at compounded interest payable annually. The interest in the first two successive years was Rs. 400 and Rs. 420. The sum is
(A) Rs. 8000
(B) Rs. 8200
(C) Rs.7500
(D) Rs. 8500
(E) Rs. 8600
Rationale: Explanation:
his means that, simple Interest on Rs.400 for 1 year = 420 - 400 = 20
Rate = (100 ×SI)/PT = (100 × 20)/(400×1) = 5%
Rs.400 is the interest on the sum for 1st year
Hence, sum = (100 × SI)/RT = (100 × 400)/(5 × 1) = Rs. 8000
Answer: Option A
Answer: (A) Rs. 8000
Question: A train 330 m long passed a pole in 11 sec. How long will it take to pass a platform 760 m long?
(A) 76 sec
(B) 89 sec
(C) 87 sec
(D) 35 sec
(E) 36 sec
Rationale: Speed = 330/11 = 30 m/sec.
Required time = (330 + 760)/30
= 36 sec.
Answer:E
Answer: (E) 36 sec
Question: 7 men, 5 women and 8 children were given as assignment of distributing 2000 books to students in a school over a period of 3 days. All of them distributed books on the 1st day. One of the 2nd day 2 women and 3 children remained absent and on the 3rd day 3 men and 5 children remained absent. If the ratio of the no. of books distributed in a day by a man, a woman & a child was 5 : 4 : 2 respectively, a total of approximately how many books were distributed on the second day?
(A) 540
(B) 560
(C) 670
(D) 650
(E) 700
Rationale: Sol. Let the books distributed by man, a woman and a child be 5x, 4x and 2x respectively.
∴ No. of books distributed in 1st day
= 7×5x+5×4x+8×2x=71x
No. of books distributed in 1Ind day
=7×5x+3×4x+5×2x=57x
And no. of books distributed in IIIrd day
=4×5x+5×4x+3×2x=46x
71x + 57x + 46x = 2000, x = 2000/174
57x=2000/174×57=650
D
Answer: (D) 650
Question: The ratio between the length and the breadth of a rectangular park is 3 : 2. If a man cycling alongthe boundary ofthe park at the speed of 12 km/hr completes one round in 8 min, then the area of the park (in sq. m) is?
(A) 13400 m
(B) 147600 m
(C) 153600 m
(D) 187500 m
(E) 196700 m
Rationale: Perimeter = Distance covered in 8 min. = 12000 x 8 m = 1600 m.
60
Let length = 3x metres and breadth = 2x metres.
Then, 2(3x + 2x) = 1600 or x = 160.
Length = 480 m and Breadth = 320 m.
Area = (480 x 320) m2 = 153600 m
C
Answer: (C) 153600 m
Question: The cost price of 8 articles is equal to the selling price of 5 articles. What is the profit percent?
(A) 30%
(B) 40%
(C) 50%
(D) 60%
(E) 70%
Rationale: 5*SP = 8*CP
SP = 1.6*CP
The profit percent is 60%.
The answer is D.
Answer: (D) 60%
Question: Efrida and Frazer who live 10 miles apart, meet at a restaurant that is directly north of Efrida's home and directly east of Frazer's home. If the restaurant is three miles closer to Efrida's home, than to Frazer's home, how many miles is the restaurant from Frazer's home?
(A) 6
(B) 7
(C) 8
(D) 10
(E) 11
Rationale: It's a simple geometry problem. Look at the diagram below:
Answer: B.
Answer: (B) 7
Question: Goldenrod and No Hope are in a horse race with 6 contestants. How many different L arrangements of finishes are there if No Hope always finishes before Goldenrod and if all of the horses finish the race?
(A)  720
(B)  360
(C)  120
(D)  24
(E)  21
Rationale: no hope finishing before goldenrod= 1/2 of the times
therefore the different L arrangements are 1/2* 6! = 360 = B
Answer: (B)  360
Question: Find a positive number which when increased by 17 is equal to 60 times the reciprocal of the number.
(A) 3
(B) 5
(C) 7
(D) 12
(E) 15
Rationale: Sol.
Let the number be x.
Then, x+17 = 60/x
⇔ x2 + 17x - 60 = 0
⇔ (x+20)(x-3) = 0
⇔ x = 3.
Answer A
Answer: (A) 3
Question: A man can row 8 kmph in still water. When the river is running at 1.2 kmph, it takes him 1 hour to row to a place and black. How far is the place?
(A) 3.58
(B) 3.68
(C) 3.78
(D) 3.88
(E) 3.98
Rationale: M = 8
S = 1.2
DS = 8 + 1.2 = 9.2
US = 8- 1.2 = 6.8
x/9.2 + x/6.8 = 1
x = 3.68.Answer: B
Answer: (B) 3.68
Question: 15 binders can bind 1400 books in 21 days. How many binders will be required to bind 1600 books in 20 days?
(A) 18
(B) 86
(C) 16
(D) 10
(E) 19
Rationale: Binders Books Days
15 1400 21
x 1600 20
x/15 = (1600/1400) * (21/20) => x
= 18
Answer: B
Answer: (B) 86
Question: In what ratio mental A at Rs.68 per kg be mixed with another metal at Rs.96 per kg so that cost of alloy (mixture) is Rs.75 per kg?
(A) 5:8
(B) 3:1
(C) 3:7
(D) 9:5
(E) 9:8
Rationale: (96-75)/(75-68)=21/7=3/1
ANSWER:B
Answer: (B) 3:1
Question: The difference between the value of a number increased by 25% and the value of the original number decreased by 30% is 22. What is the original number?
(A) 40
(B) 50
(C) 65
(D) 70
(E) 90
Rationale: Let the original # be x then 1.25x−0.7x=22 --> x=40
Answer: A.
Answer: (A) 40
Question: A cistern can be filled by a tap in 4 hours while it can be emptied by another tap in 9 hours. If both the taps are opened simultaneously, then after how much time will the cistern get filled?
(A) 4.5 hrs
(B) 5 hrs
(C) 6.5 hrs
(D) 7.2 hrs
(E) 7 hrs
Rationale: Net part filled in 1 hour = (1/4 - 1/9) = 5/36
The cistern will be filled in 36/5 hrs i.e., 7.2 hrs.
ANSWER:D
Answer: (D) 7.2 hrs
Question: We have boxes colored either red or blue. In each blue box there is a fixed number of blueberries. In each red box there is a fixed number of strawberries. If we dispose of one blue box for one additional red box, the total number of berries would increase by 15, and the difference between the total number of strawberries and the total number of blueberries would increase by 87. Each blue box contains how many blueberries?
(A) 28
(B) 30
(C) 32
(D) 34
(E) 36
Rationale: Let x be the number of blueberries in each blue box.
Then there are x+15 strawberries in each red box.
x+(x+15)=87
x = 36
The answer is E.
Answer: (E) 36
Question: The units digit of (35)^(87) + (93)^(53) is:
(A) 2
(B) 4
(C) 6
(D) 8
(E) 0
Rationale: The units digit of powers of 3, cycles in a group of 4: {3, 9, 7, 1}
53 has the form 4k+1, so the units digit of 93^53 is 3.
The units digit of powers of 5 is always 5.
3+5 = 8, so the units digit is 8.
The answer is D.
Answer: (D) 8
Question: A train covers a distance of 1000 km in 10hrs. Find the speed of the train?
(A) 100km/hr
(B) 120km/hr
(C) 150km/hr
(D) 50km/hr
(E) 75km/hr
Rationale: Speed = 1000/10 = 100km/hr
Answer is A
Answer: (A) 100km/hr
Question: The distance light travels in one year is approximately 5,870,000,000,000 miles. the distance light in 100 year is
(A) 587 x 10power9 miles
(B) 587 x 10power12 miles
(C) 587 x 10power8 miles
(D) 587 x 10power-12 miles
(E) 587 x 10power-9 miles
Rationale: the distance of the light travels in 100 years is
5,870,000,000,000 x 100 miles= 587,000,000,000,000=587 x 10 power12 miles, correct answer will be (B)
Answer: (B) 587 x 10power12 miles
Question: The breath of a rectangular landscape is 8 times its length. There is a playground in it whose area is 3200 square mtr & which is 1/9 rd of the total landscape. What is the breath of the landscape?
(A) 420
(B) 430
(C) 280
(D) 360
(E) 480
Rationale: Sol. 8x * x =9* 3200
x = 60
Length = 8* 60 = 480
E
Answer: (E) 480
Question: If Re.50 amounts to Rs.250 over a period of 30 years. What is the rate of simple interest?
(A) 13.99%
(B) 13.66%
(C) 13.33%
(D) 13.44%
(E) 13.55%
Rationale: 200 = (50*30*R)/100
R = 13.33%
Answer:C
Answer: (C) 13.33%
Question: A train 440 meters long is running with a speed of 45 kmph. The time taken by it to cross a tunnel 180 meters long is?
(A) 40.6 sec
(B) 41.6 sec
(C) 42.6 sec
(D) 49.6 sec
(E) 44.6 sec
Rationale: D = 440 + 180 =620
S = 45 * 5/18 = 12.5 mps
T = 620/12.5 = 49.6 sec
ANSWER:D
Answer: (D) 49.6 sec
Question: 4,25,49,121,169,289,
(A) 361
(B) 169
(C) 189
(D) 209
(E) 219
Rationale: 19^2= 361 because follow sequence of square of the prime numbers
ANSWER:A
Answer: (A) 361
Question: The price of commodity X increases by 45 cents every year, while the price of commodity Y increases by 20 cents every year. In 2001, the price of commodity X was $5.20 and the price of commodity Y was $7.30. In which year will the price of commodity X be 10 cents less than the price of commodity Y?
(A) 2008
(B) 2009
(C) 2010
(D) 2011
(E) 2012
Rationale: The price of commodity X increases 25 cents each year relative to commodity Y.
The price difference is $2.10 and commodity X needs to be 10 cents less than commodity Y.
$2.00 / 25 cents = 8 years
The answer is 2001 + 8 years = 2009.
The answer is B.
Answer: (B) 2009
Question: If there are 80 red and blue marbles in a jar, and the ratio of red to blue marbles is 2:3, what is the probability that, drawing twice, you will select two red marbles if you return the marbles after each draw?
(A) 1/25
(B) 2/25
(C) 3/25
(D) 4/25
(E) 21/25
Rationale: 30 red and blue marbles in a jar, and the ratio of red to blue marbles is 2:3
So, 5x=80 ---> x=16
Red marbles = 2*x = 2*16 = 32
Blue marbles = 3*x = 3*16 = 48
Prob to select a red marble = 32/80 = 2/5
Prob to select 2 red marbles with replacement = 2/5*2*5 = 4/25
Hence, answer will be D.
Answer: (D) 4/25
Question: If 2994 ÷14.5 = 172, then 29.94 ÷ 1.45 = ?
(A) 172
(B) 0.172
(C) 1.72
(D) 17.2
(E) none
Rationale: Solution
(29.94/1.45)	= 299.4/14.5
= (2994/14.5×1/10)
= 172/10
= 17.2.
Answer D
Answer: (D) 17.2
Question: John makes $45 a week from his job. He earns a raise andnow makes $75 a week. What is the % increase?
(A) 16%
(B) 46.66%
(C) 44.44%
(D) 36.98%
(E) 17%
Rationale: Increase = (20/45)*100 = (4/9)*100 = 44.44%.
C
Answer: (C) 44.44%
Question: If the price of gasoline increases by 25% and a driver intends to spend only 20% more on gasoline, by how much percent should the driver reduce the quantity of gasoline that he buys?
(A) 2%
(B) 3%
(C) 4%
(D) 5%
(E) 6%
Rationale: Let x be the amount of gasoline the driver buys originally.
Let y be the new amount of gasoline the driver should buy.
Let P be the original price per liter.
(1.25*P)y = 1.2(P*x)
y = (1.2/1.25)x = 0.96x which is a reduction of 4%.
The answer is C.
Answer: (C) 4%
Question: If a is a positive integer then 5^(2a) + (625^a)/(5^(2a)) =
(A) 25^a
(B) 24^a
(C) 2 × 25^a
(D) 55^a
(E) 5/25^a
Rationale: 5^(2a) + 625^a/ 5^(2a) = 25^a + 625^a/25^a = 25^a + (625/25)^a = 25^a + 25^a = 2 × 25^a
Answer : C
Answer: (C) 2 × 25^a
Question: A man walks at the speed of 5 km/hr and runs at the speed of 10 km/hr. How much time will the man require to cover the distance of 28 km, if he covers half (first 14 km) of his journey walking and half of his journey running ?
(A) 3.2 hrs
(B) 5.2 hrs
(C) 4.2 hrs
(D) 8.2 hrs
(E) 9.2 hrs
Rationale: C
4.2 hrs
Total time required = 14/5+14/10
28+14/10 = 4.2 hrs
Answer: (C) 4.2 hrs
Question: A and B invest money in the ratio 6:7 and they has loss of Rs.7800 at the end of year. what is the share of loss of B?
(A) Rs.4200
(B) Rs.4300
(C) Rs.4400
(D) Rs.4500
(E) None of the above
Rationale: et ratio of A and B be 6x & 7x
so net loss = 6x+7x= 7800
x=600
A=6x=6(600)=3600
B= 7x=7(600)=4200
so, B= 4200
ANSWER:A
Answer: (A) Rs.4200
Question: Maddie has 15 apples, if she give 8 to mike, how many does she have left?
(A) 1
(B) 7
(C) 3
(D) 4
(E) 5
Rationale: 15-8=7
B. 7
Answer: (B) 7
Question: During a certain two-week period, 72 percent of the movies rented from a video store were comedies, and of the remaining movies rented, there were 6 times as many dramas as action movies. If no other movies were rented during that two-week period and there were A action movies rented, then how many comedies, in terms of A, were rented during that two-week period?
(A) 1/20 A
(B) 10 A
(C) 15 A
(D) 18 A
(E) 23 A
Rationale: Movies: 72 % comedies. 28 % remaining genre.
Now in this 28 %, there are only 2 categories. Action movies and Drama Movies.
If Action = x; Drama movies = 6x. Total 7x.
7x = 28; x = 4
Action movies: 4 %
Drama movies: 24 %
we can say that out of 100z,:
comedies: 72z
action: 4z
drama: 24 z
Now action movies were A
This means:
A = 4z.
z = (A/4)
Comedies: 72z = 72 * (A/4)
18 A
D is the answer.
Answer: (D) 18 A
Question: Ashok and Pyarelal invested money together in a business and share a capital of Ashok is 1/9 of that of Pyarelal.if the incur a loss of Rs 1200 then loss of Pyarelal?
(A) 600
(B) 700
(C) 1080
(D) 900
(E) 1000
Rationale: Let the capital of Pyarelal be x, then capital of Ashok=x/9
So ratio of investment of Pyarelal and Ashok = x : x/9 =9x : x
Hence out of the total loss of 1200, loss of Pyarelal= 1200*9x/10x=1080
ANSWER:C
Answer: (C) 1080
Question: The profit earned by selling an article for 832 is equal to the loss incurred when the same article is sold for 448. What should be the sale price of the article for making 50 per cent profit?
(A) 960
(B) 1060
(C) 1,200
(D) 920
(E) None of these
Rationale: Let the profit or loss be x
and 832 – x = 448 + x or, x = 384⁄2 = 192
\ Cost price of the article = 832 – x = 448 + x = 640
\ SP of the article = 640 × 150⁄100 = 960
Answer A
Answer: (A) 960
Question: Twenty percent of Country Y's yearly exports come from fruit exports. One-sixth of all fruit exports from Country Y are orange exports. If country Y generates $2.5 million from its orange exports, how much money does it generate from its yearly total of exports?
(A) $21.25m
(B) $75m
(C) $106.25m
(D) $127.5m
(E) $153m
Rationale: 2/10*1/6*(total) = 2.5
1/30*(total) = 2.5
(total) = 2.5*30 = 75
Answer: B.
Answer: (B) $75m
Question: 8 chess players take part in a tournament. Every player plays twice with each of his opponents. How many games are to be played?
(A) 66
(B) 52
(C) 58
(D) 55
(E) 56
Rationale: Though 2*(8C2) is the correct approcah to do this, but for people like me who find Perm, Comb n Prob a nightmare, an easy approach can be used.
The first guy has to play 2 matches with the rest of 7, so he'll play 14 matches.
Similarly, second guy has to play with the rest of 6 as his 2 games with the first guy are already played. So he plays 12 matches.
This continues like this and the total matches are 14+12+10...+2
14+12+...+2 = 2(7+6+...+1) = 2((7*8)/2) = 7*8 =56.
ANSWER:E
Answer: (E) 56
Question: Thirty percent of the members of a swim club have passed the lifesaving test. Among the members who have not passed the test, 26 have taken the preparatory course and 65 have not taken the course. How many members are there in the swim club?
(A)  60
(B)  80
(C)  100
(D)  130
(E)  140
Rationale: 30% of the members have passed the test, thus 70% have not passed the test.
We also know that 65+26=91 members have not passed the test, thus 0.7*Total=91 --> Total=130.
Answer: D.
Answer: (D)  130
Question: Set A = {1, 2, 3, 4, 5, 6, e}
Which of the following possible values for e would cause Set A to have the smallest standard deviation?
(A)  1
(B)  2.5
(C)  3
(D)  3.5
(E)  7
Rationale: I agree. The mean of the set e 1,2,3,4,5,6 is 3.5 . Now if we add one extra number to the set, in order for the standard deviation to be minimum, that number must be as close as possible to the original set (1,2,3,4,5,6). Therefore we have to choose the number closest to 3,5 from the options we have, leaving D as the best choice.
Answer D.
Answer: (D)  3.5
Question: 7 people sit at the round table. In how many ways can we sit them so that Bob and Bill don't sit opposing each other?
(A) 400
(B) 420
(C) 440
(D) 460
(E) 480
Rationale: 7 People: Bob,Bill,Red,Blue,White,Pink,Purple
Round Table: T
7 Chairs: 1,2,3,4,5,6,7
Let chairs 1 and 4 be opposite each other;
Bob is sitting on 1 and Bill is sitting on 4;
The rest of the people on 2,3,5,6,7 - can rearrange themselves in 5! ways
Now, Bill and Bob swap their positions;
Bob is sitting on 4 and Bill is sitting on 1;
The rest of the people on 2,3,5,6,7 - can rearrange themselves in 5! ways
Thus total number of ways in which Bob and Bill are sitting opposite each other = 2*5! = 120*2 = 240
We have to find in how many ways they are NOT sitting opposite; subtract 240 from the total number of possible arrangements;
In circular permutation, Total number of arrangements of n people = (n-1)!
Here number of people = 7
Arrangements = (7-1)! = 6!= 720
Number of ways Bob and Bill are NOT sitting opposite = 720-240 = 480.
Answer: E
Answer: (E) 480
Question: Johnny makes $6.75 per hour at his work. If he works 10 hours, how much money will he earn?
(A) $67.50
(B) $54
(C) $28.50
(D) $12.50
(E) $9.60
Rationale: 6.75*10=67.50. Answer is A.
Answer: (A) $67.50
Question: Veena ranks 44rd from the top in a class of 182. What is her rank from the bottom if 22 students have failed the examination?
(A) 88
(B) 108
(C) 110
(D) 90
(E) 117
Rationale: total student=182
failed=22
paasd student=182-22=160
from bottom her rank is=160-44+1=117
ANSWER:E
Answer: (E) 117