divelab/Sys2Bench huggingface dataset:
Question: An observation is made on a clock and it is found that the hour hand is placed exactly at the minute mark while the minute hand is six minutes ahead it. After some time, the clock is observed again and it is found that the hour hand is exactly on another minute mark while the minute hand is seven minutes ahead of it.
Analyzing this data, can you calculate the total time that has elapsed between the two observations?
Options:
A)2hr 11min
B)1hr 11min
C)3hr 11min
D)2hr 15min
E)3hr 21min
Rationale: A
Now this question cannot be solved unless you know a fact i.e. the hour hand is exactly on the minute mark five times every hour - on the hour, 12 minutes past hour, 24 minutes past hour, 36 minutes past hour and 48 minutes past hour.
Denoting the number of hours with X and the number of minutes as Y, let us begin with the calculation.
When we have the hour hand on the minute mark, the position of hour hand:
5X + Y/12
And the position of the minute hand = Y
When the first observation was taken,
Y = Y = 5X + Y/12 + 6
Or, 60X = 11Y - 72.
With the given facts, we know for sure that Y can only be 0, 12, 24, 36 or 48.
According to which, the possible values for X and Y can be 1 and 12 respectively. Thus the time must be 1:12 when the first observation was taken.
Similarly, in the second observation, let's make the equation:
60X = 11Y - 84
Here, the possible values for X and Y here are 3 and 24 respectively. According to this, the time is 3:24 for sure.
From 1:12 to 3:24, two hours and eleven minutes have passed.
Answer: A
Question: The day of week on July 1,2000 was
Options:
A)Monday
B)Friday
C)Saturday
D)Tuesday
E)None of the above
Rationale: 1600 years:0 odd days
300 years=1 odd day
99 years=4 odd days
So till 1999 there are 5 odd days
now in 2000....2000 is a leap year
1 odd day till 1 july 2000 from jan 1 2000
so total odd days=5+1=6
So saturday
ANSWER:C
Answer: C
Question: An order was placed for the supply of a carper whose length and breadth were in the ratio of 3 : 2. Subsequently, the dimensions of the carpet were altered such that its length and breadth were in the ratio 7 : 3 but were was no change in its parameter. Find the ratio of the areas of the carpets in both the cases?
Options:
A)8:8
B)8:1
C)8:7
D)8:5
E)8:9
Rationale: Let the length and breadth of the carpet in the first case be 3x units and 2x units respectively.
Let the dimensions of the carpet in the second case be 7y, 3y units respectively.
From the data,.
2(3x + 2x) = 2(7y + 3y)
=> 5x = 10y
=> x = 2y
Required ratio of the areas of the carpet in both the cases
= 3x * 2x : 7y : 3y
= 6x2 : 21y2
= 6 * (2y)2 : 21y2
= 6 * 4y2 : 21y2
= 8:7
Answer:C
Answer: C
Question: The average waight of A,B,C is 45 Kg. The avgwgt of A & B be 40Kg & that of B,C be 43Kg. Find the wgt of B.
Options:
A)23 KG
B)43 KG
C)21 KG
D)31 KG
E)43 KG
Rationale: Sol. Let A,B,c represent their individual wgts.
Then,
A+B+C=(45*3)Kg=135Kg
A+B=(40*2)Kg=80Kg & B+C=(43*2)Kg=86Kg
B=(A+B)+(B+C)-(A+B+C)
=(80+86-135)Kg
=31Kg.
ANSWER D
Answer: D
Question: If 6x^2 + x - 12 = (gx + b)(cx + d), then |g| + |b| + |c| + |d| =
For a complete solution and more practice problems, see this blog:
http://magoosh.com/gmat/2012/algebra-on ... to-factor/
Options:
A) 10
B) 12
C) 15
D) 18
E) 20
Rationale: 6x^2+x-12 = 6x^2 + 9x -8x -12
=> 3x(2x+3) -4(2x+3)
=> (2x+3)(3x-4) = (gx+b)(cx+d)
Hence g=2, b=c=3, d=-4
So, 2+3+3+ |-4| = 2+3+3+4 = 12
Answer B.
Answer: B
Question: Out of a group of 10 contestants, 2 are to be selected at random. What is the maximum number of male contestants possible if the probability that both selected contestants are male is less than 40% ?
Options:
A) 2.1
B) 1.9
C) 1.7
D) 1.5
E) 1.6
Rationale: Let x be the number of males.
Total contestants = 10
Probability that the first contestant selected is a male = x/10
Probability that the second contestant selected is also a male = x-1/9
Total probability = x(x-1)/ 90 < 1/40 (this probability is less than 40%)
Solving for x we get, x(x-1)< 9/4. This implies that the maximum value of x can be 1.5.
Answer D!
Answer: D
Question: What is the speed of the stream if a canoe rows upstream at 6km/hr and downstream at 10km/hr
Options:
A)1 kmph
B)4 kmph
C)3 kmph
D)2 kmph
E)1.9 kmph
Rationale: Sol.
Speed of stream = 1/2(10 -6) kmph = 2 kmph.
Answer D
Answer: D
Question: Preethi has 6 flavors of ice cream in his parlor. How many options are there for Dorathy to pick a one-flavor, two-flavor, three-flavor, four-flavor, five flavor or six flavor order?
Options:
A)26
B)36
C)64
D)67
E)63
Rationale: 6C1 + 6C2+ 6C3+6C4+6C5+6C6 = 63.
Answer: E
Answer: E
Question: A is 30% more efficient than B .how much time they will working together take to complete a job which A alone could have done in 23 days?
Options:
A)25 days
B)13 days
C)14 days
D)20 days
E)15 days
Rationale: The ratio of times taken by A and B=100:130=10:13
suppose B can do work in x days
then 10:13::23:x
x=(23*13)/10
x=299/10
A's 1 day's work=1/23
B's 1 day's work=10/299
(A+B)'s 1 day's work =1/23+10/299 =23/299=1/13
A and B together can do work in 13 days
Answer(B)
Answer: B
Question: A bus from city M is traveling to city N at a constant speed while another bus is making the same journey in the opposite direction at the same constant speed. They meet in point P after driving for 2 hours. The following day the buses do the return trip at the same constant speed. One bus is delayed 24 minutes and the other leaves 36 minutes earlier. If they meet 24 miles from point P, what is the distance W between the two cities?
Options:
A)48
B)72
C)96
D)120
E)192
Rationale: Hmmm I did this question a while ago and got it wrong so trying again
Rate x time = distance.
For the initial trip lets the distance W to the midpoint be represented by P.
EQN1: R x 2 = P
For the second trip we know one bus left late and one left early. Together this is just a tricky way of saying one bus left an hour after the other. We know the total trip takes 4 hours (since getting to P is 2 hours). The second trip can be represented by:
Since the trip takes 4 hours if a bus leaves one hour early, the reminaining 3 hours are split between the two buses, ie. 1 + 3/2 = 2.5
EQN2: R x 2.5 = P + 24
EQN2-EQN1 : 0.5R=24
R=48
So the distance is rate x time = 48 x 4 = 192.
ANS = E
Answer: E
Question: A bottle contains a certain solution. In the bottled solution, the ratio of water to soap is 3:2, and the ratio of soap to salt is three times this ratio. The solution is poured into an open container, and after some time, the ratio of water to soap in the open container is halved by water evaporation. At that time, what is the ratio of water to salt in the solution?
Options:
A)1:1
B)2:3
C)3:2
D)9:4
E)27:8
Rationale: Water:soap = 3:2
Soap:Salt=9:2
=> For 9 soap, salt = 2
=> For 2 Soap, salt = (2/9)*2 = 4/9
So, water:soap:salt = 3:2:4/9 = 27:18:4
After open container, water:soap:salt = 13.5:18:4
So, water:salt = 13.5:4 = 27:8
ANSWER:E
Answer: E
Question: Two cars cover the same distance at the speed of 60 and 64 kmps respectively. Find the distance traveled by them if the slower car takes 1 hour more than the faster car?
Options:
A)278
B)277
C)960
D)278
E)261
Rationale: 60(x + 1) = 64x
X = 15
60 * 16 = 960 km
Answer:C
Answer: C
Question: The traffic lights at three different road crossings change after every 48 sec., 72 sec and 108 sec.respectively .If they all change simultaneously at 8:20:00 hours,then at what time they again change simultaneously .
Options:
A)8:29:12 hrs
B)8:22:12 hrs
C)8:25:12 hrs
D)8:27:12 hrs
E)8:21:12 hrs
Rationale: Interval of change = (L.C.M of 48,72,108)sec.=432sec.
So, the lights will agin change simultaneously after every 432 seconds i.e,7 min.12sec
Hence , next simultaneous change will take place at 8:27:12 hrs
Answer is D.
Answer: D
Question: Find the missing value?
19 28 23 32
40 31 36 27
? 44 39 48
Options:
A)31
B)32
C)33
D)34
E)35
Rationale: 19 (+9) 28 (-5) 23 (+9) 32
40 (-9) 31 (+5) 36 (-9) 27
? (+9) 44 (-5) 39 (+9) 48
hence ?+9=44
?=35
ANSWER:E
Answer: E
Question: Rs. 1300 is divided into three parts A, B and C. How much A is more than C if their ratio is 1/2:1/3:1/4?
Options:
A)300
B)992
C)772
D)552
E)312
Rationale: 1/2:1/3:1/4 = 6:4:3
3/13*1300 = 300
Answer: A
Answer: A
Question: Two pens and three pencils cost Rs 86. four Pens and a pencil cost Rs. 112. find the cost of a pen and that of a pencil.
Options:
A)12
B)10
C)15
D)19
E)20
Rationale: Let the cost of a pen ands a pencil be Rs. X and Rs. Y respectively.
Then, 2x + 3y = 86 ….(i) and 4x + y =112.
Solving (i) and (ii), we get: x = 25 and y = 12.
Cost of a pen =Rs. 25 and the cost of a pencil =Rs. 12.
Answer is A.
Answer: A
Question: The cost price of an article is 70% of the marked price. Calculate the gain percent after allowing a discount of 10%.
Options:
A)13.6%
B)28.6%
C)35.6%
D)42.3%
E)none
Rationale: Sol.
Let marked price = Rs. 100. Then, C.P. = Rs. 70. S.P = Rs. 90.
âˆ´ Gain % = [20/70 * 100]% = 28.6%.
Answer B
Answer: B
Question: Solve the quickfire maths brain teaser âˆš49% = ?
Options:
A)30%
B)40%
C)70%
D)19%
E)29%
Rationale: âˆš49%
=> âˆš49/âˆš100
=> 7/10
=> 70/100
=> 70%
C
Answer: C
Question: There are 13person among whom 2are brother. The total no.of ways in which these persons can be seated around a round table so that exactly 1person sit between the brothers, is equal to?
Options:
A)4!*2!
B)7!*2!
C)6!*1!
D)10!*2!
E)5!*1!
Rationale: Total number of ways = 10!*2!.
D
Answer: D
Question: The probability of selecting face card of any color from 52 cards
Options:
A)1/13
B)2/13
C)3/13
D)4/13
E)5/13
Rationale: king queen and jack are the face cards
there are totally 12 face cards in a suit
probability = 12/52 = 3/13
ANSWER:C
Answer: C
Question: If a certain number is divisible by 36 and 52, it is NOT necessarily divisible by which of the following?
Options:
A)4
B)6
C)13
D)16
E)18
Rationale: If a certain number is divisible by 36 and 52, it is NOT necessarily divisible by which of the following?
let the certain number be 468, which is both divisible by 36 and 52.
468/16 =117/4
D. 16
Answer: D
Question: A lady builds 8cm length, 15cm width, and 5cm height box using 10cubic cm cubes. What is the minimum number of cubes required to build the box?
Options:
A)107
B)60
C)70
D)89
E)78
Rationale: Number of cubes required = Volume of box/Volume of cube
= 8*15*5/10
=60 cubes
ANSWER:B
Answer: B
Question: A box contains 20 electric bulbs, out of which 4 are defective. Two bulbs are chosen at random form this box. The probability that at least one of these is defective is:
Options:
A)10/19
B)7/19
C)17/19
D)19/19
E)14/19
Rationale: P(none is defective)=16c2/20c2
=12/19
P( at least one is defective)= 1-12/19
=7/19
ANSWER B 7/19
Answer: B
Question: Working together at their respective constant rates, Machine A and Machine B can produce 600 units in 8 hours. Working alone, Machine B would complete that same output in 50% more time. If Machine A were to work on its own for an 8-hour shift, what percent of the 600 unit total would it produce?
Options:
A)25
B)37
C)50
D)30
E)75
Rationale: 1/A+1/B= 1/T
1/A +1/12= 1/8 (50% more of 8 is 12)
1/A= 1/24
Machine A can produce 600 units in 24 hrs, so it can produce 600*8/24= 200 units is 8 hrs.
200 is 30% of 600.
D is the answer
Answer: D
Question: A train crosses a platform of 150 m in 15 sec, same train crosses another platform of length 250 m in 20 sec. then find the length of the train?
Options:
A)150m
B)159m
C)750m
D)180m
E)159m
Rationale: Length of the train be ‘X’
X + 150/15 = X + 250/20
4X + 600 = 3X + 750
X = 150m
Answer:A
Answer: A
Question: Andrew travelling to 7 cities. Gasoline prices varied from city to city. What is the median gasoline price?
Options:
A)$1
B)$1.84
C)$2.54
D)$2.65
E)$3
Rationale: Ordering the data from least to greatest, we get:
$1.61, $1.75, $1.79, $1.84, $1.96, $2.09, $2.11
The median gasoline price is $1.84. (There were 3 states with higher gasoline prices and 3 with lower prices.)
B
Answer: B
Question: Three cards are drawn successively, without replacement from a pack of 52 well shuffled cards.
What is the probability that first two cards are queens and the third card drawn is an ace?
Options:
A)2/5521
B)2/5529
C)5525/2
D)1/5525
E)2/5525
Rationale: Let Q denote the event that the card drawn is queen and A be the event that
the card drawn is an ace. Clearly, we have to find P (QQA)
Now P(Q) = 4/52
Also, P (Q|Q) is the probability of second queen with the condition that one queen has
already been drawn. Now there are three queen in (52 - 1) = 51 cards.
Therefore P(Q|Q) = 3/51
P(A|QQ) is the probability of third drawn card to be an ace, with the condition
that two queens have already been drawn. Now there are four aces in left 50 cards.
Therefore P(A|QQ) = 4/50
By multiplication law of probability, we have
P(QQA) = P(Q) P(Q|Q) P(A|QQ)
= 4/52 × 3/51 × 4/50
= 2/5525.
E
Answer: E
Question: NHAI employs 100 men to build a highway of 2km in 50 days working 8 hours a day.if in 25 days they completed 1/3 part of work .than how many more emploies should NHAI hire to finish it in time working 10 hours a day
Options:
A)60
B)70
C)80
D)50
E)40
Rationale: (M1*D1*H1)/W1 = (M2*D2*H2)/W2
(100*25*8)/(1/3) =((100+a)*25*10))/(2/3)
160=100+a
a=60
ANSWER:A
Answer: A
Question: n what ratio should a variety of rice costing Rs. 6 per kg be mixed with another variety of rice costing Rs. 8.75 per kg to obtain a mixture costing Rs. 7.50 per kg?
Options:
A)2/7
B)5/6
C)3/4
D)1/5
E)6/16
Rationale: Explanation:
Let us say the ratio of the quantities of cheaper and dearer varieties = x : y
By the rule of allegation, x/y = (87.5 - 7.50) / (7.50 - 6) = 5/6
Correct Option :B
Answer: B
Question: The wages earned by Robin is 38% more than that earned by Erica. The wages earned by Charles is 60% more than that earned by Erica. How much % is the wages earned by Charles more than that earned by Robin?
Options:
A)23%
B)27.53%
C)30%
D)50%
E)100%
Rationale: Explanatory Answer
Let the wages earned by Erica be $100
Then, wages earned by Robin and Charles will be $138 and $160 respectively.
Charles earns $38 more than Robin who earns $138.
Therefore, Charles' wage is 38/138*100 = 27.53%.
The correct choice is (B)
Answer: B
Question: There are three departments having students 68,58,24 .In an exam they have to be seated in rooms such that each room has equal number of students and each room has students of one type only (No mixing of departments). Find the minimum number of rooms required?
Options:
A)73
B)74
C)75
D)76
E)77
Rationale: WE NEED TO TAKE GCD WHICH IS 2
THUS ALL THE ROOMS WILL HAVE 2 STUDENTS OF THE SAME DEPT
1) 68/2 = 34
2) 58/2 = 29
3) 24/2 = 12
TOTAL NO. OF MIN ROOMS REQD = 34+12+29 = 75
ANSWER:C
Answer: C
Question: An accurate clock shows 8 o'clock in the morning. Through how many degrees will the hour hand rotate when the clock shows 12 o'clock noon?
Options:
A)30
B)60
C)90
D)120
E)150
Rationale: The hour hand will move 4/12 of a circle.
(4/12)*360 = 120 degrees.
The answer is D.
Answer: D
Question: Which of the following integers is the square of an integer?
Options:
A)73,410,624
B)63,398,748
C)54,113,892
D)42,785,337
E)31,298,793
Rationale: CONCEPT: The unit digit of any Perfect Square can't be 2 or 3 or 7 or 8
Hence Option B, C D and E can be ruled out
Answer: option A
Answer: A
Question: The perimeter of a triangle is 32 cm and the inradius of the triangle is 2.5 cm. What is the area of the triangle
Options:
A)A)40
B)B)828
C)C)729
D)D)34
E)E)35
Rationale: Explanation:
Area of a triangle = r * s
Where r is the inradius and s is the semi perimeter of the triangle.
Area of triangle = 2.5 * 32/2 = 40 cm2
Answer: Option A
Answer: A
Question: A coin is tossed 4 times. What is the probability t that the number of Heads is equal to the number of Tails?
Options:
A)1/8
B)1/4
C)3/8
D)1/2
E)9/16
Rationale: We have to find the probability that we get 2 heads and 2 tails in 4 tosses of the coin.
Using the binary formula and defining a head as a success,
P(2 heads in 4 tosses) = 4C2* (1/2)^2 * (1/2)^2
t= 6/16
= 3/8
The answer is therefore (C)
Answer: C
Question: A trader mixes 25 kg of rice at Rs. 40 per kg with 25 kg of rice of other variety at Rs. 20 per kg and sells the mixture at Rs. 40 per kg. His profit percent is:
Options:
A)No profit, no loss
B)33.33%
C)8%
D)10%
E)None of these
Rationale: C.P. of 56 kg rice = Rs. (25 x 40 + 25 x 20) = Rs. (1000 + 500) = Rs. 1500.
S.P. of 56 kg rice = Rs. (50x 40) = Rs. 2000
Gain =500/1500x100% = 33.33%
Answer: Option B
Answer: B
Question: In a vacant lot a man have 5 goat which eat in 2 days all the bush of 1/4 part of the lot, full of bushes. If the man added 10 goats to the lot and all of them will eat the weed at the same rate, how many days will take to all the goats eat all the bushes of the lot, since the first day?
Options:
A) 8 days
B) 7 days
C) 6 days
D) 5 days
E) 4 days
Rationale: We have that: 5 goats ----- 2 days, (5+10) G ----- X d, that is: (X d/ 5G) = (2 d/15G), then: X d = (2 d/15G)5G = (2/3)d. Is to say, the 15 goats eat the same quantity in 2/3 days; it is only 1/4 of the lot. Then, all the lot is: L = L1 + L2 + L3 + L4= 2 d + 3(2/3)d = (2 + 2) d = 4 days. Answer E.
Answer: E
Question: In a two-digit number, if it is known that its unit's digit exceeds its ten's digit by 2 and that the product of the given number and the sum of its digits is equal to 144, then the number is:
Options:
A)24
B)26
C)42
D)46
E)52
Rationale: Explanation:
Let the ten's digit be x. Then, unit's digit = x + 2. Number = 10x + (x + 2) = 11x + 2
Sum of digits = x + (x + 2) = 2x + 2
(11x + 2)(2x + 2) = 144
2x2 + 26x - 140 = 0
(x - 2)(11x + 35) = 0
x = 2
Hence, required number = 11x + 2 = 24.
ANSWER IS A
Answer: A
Question: According to the direction on a can of frozen orange juice concentrate is to be mixed with 3 cans of water to make orange juice . How many 12 - ounce cans of the concentrate are required to prepare 272 6-ounce servings of orange juice?
Options:
A)25
B)34
C)50
D)67
E)100
Rationale: Orange juice concentrate: water::1:3
total quantity of orange juice = 272*6 = 1632 oz
so Orange juice concentrate: water :: 408 oz:1224 oz
no. of 12 oz can = 408 oz/12 oz = 34
Answer B, 34 cans
Answer: B
Question: A company has a job to prepare certain number of cans and there are three machines A, B and C for this job. A can complete the job in 3 days, B can complete the job in 4 days and C can complete the job in 6 days. How many days the company will it take to complete the job if all the machines are used simultaneously?
Options:
A)4 days
B)4/3 days
C)3 days
D)12days
E)14 days
Rationale: Let the total number of cans to be prepared be 12.
The number of cans prepared by A in 1 day = 4.
The number of cans prepared by B in 1 day = 3.
The number of cans prepared by C in 1 day = 2.
Thus, the total number of cans that can be prepared by all the machines working simultaneously in a single day = 9.
Therefore, the number of days taken to complete the whole work = 12/9 = 4/3 days.
ANSWER:B
Answer: B
Question: The captain of a cricket team of 11 members is 26 years old and the wicket keeper is 9 years older. If the ages of these two are excluded, the average age of the remaining players is one year less than the average age of the whole team. What is the average age of the team?
Options:
A)23 years
B)24 years
C)25 years
D)26 years
E)27 years
Rationale: EXPLANATION
Let the average age of the whole team by x years.
11x â€“ (26 + 38) = 9(x -1)
11x â€“ 9x = 52
2x = 52
x = 26.
So, average age of the team is 26 years.
Answer D
Answer: D
Question: A man purchases 2 pens for $ 56. He sells one at 20% profit and the other at a loss of 15%. He neither gains nor loses on the whole. Thus, the cost price of two watches are :
Options:
A)$ 24 and $ 32
B)$32 and $ 24
C)$56and $32
D)$56 and $24
E)$32 and $ 56
Rationale: x + y = 56--- (1)
1.20x + 0.85y = 56 --- (2)
(2) - (1) --> 0.20x - 0.15y = 0
20x = 15y
x/y = 3/4= (3*8)/(4*8) = 24/32
Answer:A
Answer: A
Question: A rectangular block 12cm by 20cm by 36cm is cut into an exact number of equal cubes. Find the least possible number of cubes?
Options:
A)135
B)10
C)15
D)40
E)22
Rationale: Volume of the block = 12*20*36 = 8640 cm^3
Side of the largest cube = H.C.F of 12,20,36 = 4cm
Volume of the cube = 4*4*4= 64 cm^3
Number of cubes = 8640/64 = 135
Answer is A
Answer: A
Question: Ron scored 344 marks out of 400 marks and his elder brother Ben scored 582 marks out of 600 marks. Who scored percentage is better?
Options:
A)97
B)21
C)28
D)26
E)19
Rationale: Percentage of marks scored by Ron = (344/400 × 100) %
= (34400/400) %
= (344/4) %
= 86 %
Percentage of marks scored by Ben = (582/600 × 100) %
= (58200/600) %
= (582/6) %
= 97 %
Hence, the percentage marks scored by Ben is better.
Answer:A
Answer: A
Question: The sum of two consecutive number is 109. Which is the larger number?
Options:
A)42
B)43
C)44
D)45
E)55
Rationale: Let consecutive number be x, x+1
Therefore sum of the consecutive number is x + x+1=109
2x+1=109
2x=108
x=54
Therefore larger number is x+1=55
ANSWER:E
Answer: E
Question: It takes a boat 3 hours to travel down a river from point A to point B, and 5 hours to travel up the river from B to A. How long would it take the same boat to go from A to B in still water?
Options:
A)3 hours and 45 minutes.
B)2 hours and 32 minutes.
C)4 hours and 54 minutes.
D)6 hours and 26 minutes.
E)5 hours and 59 minutes.
Rationale: Let: S be the speed of the boat in still water, r be the rate of the water current and d the distance between A and B.
d = 3(S + r) : boat traveling down river
d = 5(S - r) : boat traveling up river
3(S + r) = 5(S - r)
r = S / 4 : solve above equation for r
d = 3(S + S/4) : substitute r by S/4 in equation B
d / S = 3.75 hours = 3 hours and 45 minutes.
correct answer A
Answer: A
Question: There are two groups of students in the sixth grade. There are 30 students in group A, and 50 students in group B. If, on a particular day, 20% of the students in group A forget their homework, and 12% of the students in group B forget their homework, then what percentage of the sixth graders forgot their homework?
Options:
A)13%
B)14%
C)15%
D)16%
E)17%
Rationale: Total students = 30 + 50 = 80
20% of 30 = 6
12& of 50 = 6
Total students who forget homework = 6+6 = 12
Percentage =1280∗100=15=12/80∗100=15	;Answer = C = 15%
Answer: C
Question: Every day, the value of a stock rises by exactly two dollars in the morning, and
then falls by exactly one dollar in the afternoon. If the stock's value at the start of the first
day is $100, on what day will the stock's value first reach $200?
Options:
A)50
B)99
C)100
D)101
E)200
Rationale: Note that each day the stock is worth $1 more than on the previous day, and that
on the first day it rises to $102 and then falls to $101. Therefore, on the nth day, the stock's
value rises to n + 101 dollars in the morning and falls to n + 100 dollars in the afternoon.
The solution is therefore the smallest n for which n+101 = 200, or n = 99. In particular,
the stock will be $200 in the middle of day 99, although not at the end of this day.
correct answer B
Answer: B
Question: A sum of money becomes double itself in 8 years at simple interest. How many times will it become 16 years at the same rate?
Options:
A)1
B)2
C)3
D)4
E)5
Rationale: P ---- 2P ---- 8 years4P ---- 16 years Answer: D
Answer: D
Question: Excluding stoppages, the speed of a train is 42 kmph and including stoppages it is 36 kmph. Of how many minutes does the train stop per hour?
Options:
A)7.5
B)8.5
C)9.5
D)4.5
E)6.5
Rationale: T = 6/42 * 60 = 8.5
ANSWER:B
Answer: B
Question: The average of 9 results is 50. If the average of first 4 results is 45 and that of the last six is 48, find the 5th result?
Options:
A)15
B)20
C)35
D)18
E)22
Rationale: Sixth result = 45*5 + 48*5 - 50*9 = 15
Answer is A
Answer: A
Question: The average age of 25 students in a class is 12 years. 15 students whose average age is 10 years joined them. What is the present average age.
Options:
A)13
B)12.6
C)11.25
D)12
E)13
Rationale: Explanation :
Solution: Present average = ax + by/ a + b
= 25*12 + 15*10/25+15 years
=300 + 150/ 40 => 450/40 => 11.25.
Answer : C
Answer: C