RikoteMaster/aqua-rat-mcqa huggingface dataset:
Question: In a class of 5 students, average weight of the 4 lightest students is 40 kgs, Average weight of the 4 heaviest students is 45 kgs. What is the difference between the the maximum and minimum possible average weight overall?
A.2.8 kgs
B.3.2 kgs
C.3 kgs
D.4 kgs
Answer: D.4 kgs
Explanation: DETAILED SOLUTION
If there are an odd number of terms, say, 2n + 1, then the median is the middle term. And if average is lesser than the middle term, there will at least be n + 1 terms greater than the average. So, there will be more terms above the average than below it.
However, this need not be the case when there are an even number of terms. When there are 2n distinct terms, n of them will be greater than the median and n will be lesser than the median. The average of these two terms can be such that there are n terms above the average and n below it.
For instance, if the numbers are 0, 1, 7, 7.5. The median is 4, average is 3.875. Average is less than the median. And there are more 2 numbers above the average and 2 below the average.
Correct Answer: Median is 4, average is 3.875.
Correct Answer: D
Question: A library has an average of 1000 visitors on Sundays and 700 on other days. The average number of visitors per day in a month of 30 days beginning with a Sunday is :
A.740
B.750
C.760
D.770
Answer: B.750
Explanation: Explanation:
Since the month begins with a Sunday, so there will be five Sundays in the month,
Required average = (1000 * 5 + 700 * 25) / 30 = 22500/30 = 750
Answer: B) 750
Question: A and B started a partnership business investing some amount in the ratio of 3 : 5. C joined then after 3 months with an amount equal to that of B. In what proportion should the profit at the end of one year be distributed among A, B and C?
A.4 : 9 : 8
B.5 : 7 : 4
C.6 : 10 : 7.5
D.7 : 9: 4
Answer: C.6 : 10 : 7.5
Explanation: Let the initial investments of A and B be 3x and 5x.
A : B : C = (3x x 12) : (5x x 12) : (5x x 9) = 36 : 60 : 45
= 6 : 10 : 7.5.
ANSWER :C
Question: A student has to obtain 33% of the total marks to pass. He got 125 marks and failed by 40 marks. The maximum marks are?
A.450
B.300
C.500
D.610
Answer: C.500
Explanation: Let the maximum marks be x
Then, 33% of x = 125+40
33x/100 = 165
x = 500
Answer is C
Question: A total of 30 percent of the geese included in a certain migration study were male. If some of the geese migrated during the study and 10 percent of the migrating geese were male, what was the ratio of the migration rate for the male geese to the migration rate for the female geese? [Migration rate for geese of a certain sex = (number of geese of that sex migrating) / (total number of geese of that sex)]
A.1/4
B.7/12
C.2/3
D.7/27
Answer: D.7/27
Explanation: Let' take the Number of geese to be 100.
Male = 30. Female = 70.
Now the second part of the Q, Let's take the Number migrated to be 20.
So we have 20 geese that migrated and out of that 10% are male i.e 10/100 *20 = 2 Geese (Males)
And now we know out of the total 20 geese , 2 are male , then 18 have to be female.
Now the ratio part , Male Geese Ratios = 2/30 = 1/15. - A
Female Geese Ratios =18/70=9/35 - B
Cross Multiply Equations A and B and you get = 7/27.
Ans D
Question: If Mel saved more than $10 by purchasing a sweater at a 15 percent discount, what is the smallest amount the original price of the sweater could be, to the nearest dollar?
A.45
B.67
C.75
D.83
Answer: B.67
Explanation: We are told that 15 percent discount from the original price is more than $10:
0.15*{price} > 10;
{price} > 1,000/15;
{price} > 66 2/3.
Answer: B.
Question: If the average marks of three batches of 45, 60 and 45 students respectively is 50, 55 and 60, then the average marks of all the students is
A.53.33
B.54.68
C.55
D.57
Answer: C.55
Explanation: Sol.
Required average = [55x50 + 60x55 + 45x60 / 45 + 60 + 45]
= [2250 + 3300 + 2700 / 150]
= 8250 / 150 = 55
Answer C
Question: Raj has bought the product and sold it for a profit of Rs.30. His cost of buying and selling is in the ratio of 8:9 respectively. How much did Raj spent for buying A?
A.200
B.240
C.250
D.270
Answer: B.240
Explanation: Let cost of buying of product A be x, (x+30/x)=9/8
Up on cross multiplication and solving for x, we get x=240
Answer: B
Question: A small company employs 3 men and 5 women. If a team of 4 employees is to be randomly selected to organize the company retreat, what is the probability that the team will have exactly 2 women?
A.1/14
B.1/7
C.2/7
D.3/7
Answer: D.3/7
Explanation: P=Favorable outcomes / Total # of outcomes
Favorable outcomes: 2 women and 2 men = C^2/5∗C^2/3=30
Total # of outcomes: 4 people out of 5+3=8 = C^4/8=70
P=30/70=3/7
Answer: D.
Question: A truck owner will refuel his vehicle at a rate of 2 gallons of diesel fuel every 5 seconds. If diesel fuel costs $ 2 per gallon, how long will it take for the truck owner to refuel his vehicle with $ 100 worth of diesel fuel?
A.20 seconds
B.2 minute 5 seconds
C.1 minute 20 seconds
D.20 minutes
Answer: B.2 minute 5 seconds
Explanation: 2 gal / 5 sec
$2 / gal
$100/$2 = 502 gal
2 gal / 5 sec with 50 gal = 125 sec
B. 2 minute 5 seconds
Question: If a is an odd integer and b is an odd integer which of the following must not be an odd integer :
A.a/b
B.ab
C.2a+b
D.2(a+b)
Answer: D.2(a+b)
Explanation: only when two odd number added then we get even number.
Therefore answer is D
Question: A jogger running at 9 kmph alongside a railway track in 240 metres ahead of the engine of a 120 metres long train running at 45 kmph in the same direction.In how much time will the train pass the jogger?
A.3.6 sec
B.18 sec
C.36 sec
D.72 sec
Answer: C.36 sec
Explanation: speed of the train relative to jogger = (45-9)km/hr=36km/hr.
(36*5/8)m/sec.
10m/sec.
Distance to be covered = (240 + 120) m = 360 m.
time taken =(360/10)sec=36sec.
Answer: C
Question: Two people measure each other's height, the height of the taller person is H and the height of the other person is L. If the difference in their heights is equal to the average height, what is the Value of H/L
A.1/3.
B.1/2.
C.2.
D.3.
Answer: D.3.
Explanation: Difference = Average
H - L = (H + L)/2,
Solving for H/L gives 3. A quick check, H be 21 and L be 7, 21- 7= (21 + 7 )/2
D
Question: 10 business executives and 7 chairmen meet at a conference. If each business executive shakes the hand of every other business executive and every chairman once, and each chairman shakes the hand of each of the business executives but not the other chairmen, how many handshakes would take place?
A.144
B.131
C.115
D.90
Answer: C.115
Explanation: there are 10 business exec and in each handshake 2 business execs are involved.
hence 10C2=45
Also, each of 10 exec will shake hand with every 7 other chairmen for total of 70 handshake.
total=45+70=115
ANS: C
Question: For all positive integers m and v, the expression m Θ v represents the remainder when m is divided by v. What is the value of (( 90 Θ 33 ) Θ 17 ) - ( 97 Θ (33 Θ 17)) ?
A.0
B.2
C.4
D.6
Answer: D.6
Explanation: (( 90 Θ 33 ) Θ 17 )
The remainder of 90 divided by 33 is 24;
The remainder of 24 divided by 17 is 7;
( 97 Θ (33 Θ 17))
The remainder of 33 divided by 17 is 16;
The remainder of 97 divided by 16 is 1.
7 - 1 = 6.
Answer: D.
Question: At what time, in minutes, between 3 o'clock and 4 o'clock, both the needles will coincide each other?
A.16 4/19
B.16 4/18
C.16 4/10
D.16 4/11
Answer: D.16 4/11
Explanation: Formula : θ=∣∣∣30h−112m∣∣∣θ=|30h−112m|
Here angle is 0. So
11/2 m – 30 h = 0
11/2 m – 30 × 3 = 0
m = 180/11
= 16 4/11
Ans:: D
Question: In a barrel of juice there is 60 liters; in a barrel of beer there are 80 liters. If the price ratio between barrels of juice to a barrel of beer is 3:4, what is the price ratio between one liter of juice and one liter of beer?
A.3:2.
B.1:1.
C.3:1.
D.4:3.
Answer: B.1:1.
Explanation: Juice barrel : beer Barrel = 60:80 i.e. 3:8
price of Juice : Price of Beer = 3 : 4
so for 6/8 costs 3/4, ie 6J / 8B = 3/4.
Solving for J/B, we get 2:2=1:1
Answer B.
Question: A rectangular field is to be fenced on three sides leaving a side of 20 feet uncovered.If the area of the field is 680 sq.ft, how many feet of fencing will be required?
A.34
B.40
C.68
D.88
Answer: D.88
Explanation: Solution
We have:L =20 ft and lb = 680 sq.ft	b = 34ft
Length of fencing	= (l + 2b)
= (20 + 68)ft
= 88 ft.
Answer D
Question: A river 2m deep and 45 m wide is flowing at the rate of 3 kmph the amount of water that runs into the sea per minute is?
A.4500 M3
B.4580 M3
C.I8500 M3
D.4900 M3
Answer: A.4500 M3
Explanation: Explanation:
(3000 * 2 * 5)/60 = 4500 M3
Answer: Option A
Question: Two wheels are connected via a conveyor belt. The larger wheel has a 36cm diameter and the smaller wheel has a 24cm diameter. In order for the conveyor belt to work smoothly, each wheel must rotate the exact same number of centimetres per minute. If the larger wheel makes r revolution per minute, how many revolutions does the smaller wheel make per hour in terms of r?
A.1280π
B.75r
C.48r
D.90r
Answer: D.90r
Explanation: Interesting to note that the larger wheel has a diameter of 36 (6*6) while the smaller one has a diameter of 24 (6*4)...
If the large wheel has a diameter of 36 and the small wheel, 24, then their circumferences are 36pi and 24pi respectively. In order for them to move the conveyor belt at the same rate, the smaller wheel would need to rotate 1.5 times as fast as the larger wheel. Lets say the large wheel makes 10 revolutions per minute, the smaller wheel would need to make 10*1.5 = 15 revolutions per minute. If the large wheel makes 10 revolutions per minute it makes 600 per hour. Therefore, the smaller wheel would need to make 600*1.5 = 900 revolutions per hour.
If r = 10, then the answer choice must be d.
D. 90r
Question: Ramesh can finish a work in 20 days and Sushil in 25 days. They both work together for 5 days and then Sushil goes away. In how many days will Ramesh complete the remaining work?
A.12 days
B.5 days
C.8 days
D.11 days
Answer: D.11 days
Explanation: Answer: Option D
(5 + x)/20 + 5/25 = 1 => x = 11 days
Question: Ajay can complete a piece of work in 4 days. Balu takes double the time taken by Ajay, Charan takes double that of Balu, and Danush takes double that of Charan to complete the same task. They are paired in groups of two each. One pair takes two thirds the time needed by the second pair-to complete the work. Which is the first pair?
A.A, B
B.A, C
C.B, C
D.A, D
Answer: D.A, D
Explanation: Time taken by Ajay, Balu, Charan, Dhanush is 4 days, 8 days, 16 days and 32 days respectively.
Therefore, grouping Ajay and Dhanush work will be two third of the work that will be completed by grouping Balu and Charan.
ANSWER:D
Question: A Bell Curve (Normal Distribution) has a mean of − 1 and a standard deviation of 1/8 . How many integer values M are within three standard deviations of the mean?
A.0
B.1
C.3
D.6
Answer: B.1
Explanation: Got the question correctly -- the second item -- [highlight]bthe list of elements in the set is required.[/highlight] is not required.
With the new information, there is only one integer value (-1) that is between (-1.375, -0.625) i.e., falls within the three 3 SD range.B
Question: What is the units digit of 2222^(555)*3333^(222)?
A.0
B.2
C.4
D.6
Answer: B.2
Explanation: Each of the other explanations to this question has properly explained that you need to break down the calculation into pieces and figure out the repeatingpatternof the units digits.
Here's another way to organize the information.
We're given [(2222)^333][(3333)^222]
We can 'combine' some of the pieces and rewrite this product as....
([(2222)(3333)]^222) [(2222)^111]
(2222)(3333) = a big number that ends in a 6
Taking a number that ends in a 6 and raising it to a power creates a nice pattern:
6^1 = 6
6^2 = 36
6^3 = 216
Etc.
Thus, we know that ([(2222)(3333)]^222) will be a gigantic number that ends in a 6.
2^111 requires us to figure out thecycleof the units digit...
2^1 = 2
2^2 = 4
2^3 = 8
2^4 = 16
2^5 = 32
2^6 = 64
2^7 = 128
2^8 = 256
So, every 4powers, the pattern of the units digits repeats (2, 4, 8, 6.....2, 4, 8, 6....).
111 = 27 sets of 4 with a remainder of 3....
This means that 2^111 = a big number that ends in an 8
So we have to multiply a big number that ends in a 6 and a big number that ends in an 8.
(6)(8) = 48, so the final product will be a gigantic number that ends in an 2.
Final Answer:
B
Question: A man swims downstream 30 km and upstream 18 km taking 3 hours each time, what is the speed of the man in still water?
A.7
B.8
C.5
D.2
Answer: B.8
Explanation: 30 --- 3 DS = 10
? ---- 1
18 ---- 3 US = 6
? ---- 1 M = ?
M = (10 + 6)/2 = 8
Answer:B
Question: A certain library assesses fines for overdue books as follows. On the first day that a book is overdue, the total fine is $0.20. For each additional day that the book is overdue, the total fine is either increased by $0.30 or doubled, whichever results in the lesser amount. What is the total for a book on the third day it is overdue?
A.$0.60
B.$0.70
C.$0.80
D.$0.90
Answer: B.$0.70
Explanation: 1st day fine - 0.2
2nd day fine - 0.2*2 = 0.4 (as doubling gives lower value)
3rd day fine - 0.4+3 = 0.7 (as doubling gives higher value)
Answer: B.
Question: The sides of a rectangle are in the ratio of 6 : 5 and its area is 1331 sq.m. Find the perimeter of rectangle.
A.121
B.123
C.125
D.122
Answer: A.121
Explanation: Let 6x and 5x be sides of the rectangle
6x × 5x = 1331
11xpower2 = 1331
xpower2 = 1331/11 = 121 => x = 11
Length = 6x = 6 × 11 = 66
Breadth = 5x => 5 × 11 = 55
Perimeter = 2 (l+b) => 2 (66+55) = 121 m
Answer is A.
Question: A CAN FINISH A WORK IN 21 DAYS AND B CAN DO THE SAME WORK IN15 DAYS. B WORKED FOR 10 DAYS AND LEFT THE JOB. IN HOW MANY DAYS, A ALONE CAN FINISH THE REMAINING WORK?
A.5
B.5 1/2
C.7
D.8
Answer: C.7
Explanation: B'S 10 DAY'S WORK=(1/15*10)=2/3 REMAINING WORK = (1-2/3)=1/3
NOW, 1/18 WORK IS DONE BY A IN 1 DAY
1/3 WORK IS DONE BY A IN (21*1/3)=7 DAYS.
CORRECT OPTION:C
Question: The volume of a large cube is 125 cubic inches. A new
shape is formed by removing a smaller cube from one
corner of the large cube. The surface area of this new
shape in square inches is
A.120
B.150
C.180
D.225
Answer: B.150
Explanation: Note that the surface area of the shape is the same as the surface area of the
large cube. Also, the large cube has side 5, and surface area 6 × 5-2round = 150.
correct answer B
Question: The first four numbers in a regular sequence are 4, 10, 22, and 46. What is the next number in the sequence?
A.94
B.54
C.176
D.82
Answer: A.94
Explanation: it is a good Q to learn to pick up number properties in the given set, even if we do not get a Q on these line in actuals..
when we see the sequence 4, 10, 22, 46, we see that each succeeding number is some value more than twice the previous number..
10=2*4+2..
22=2*10+2..
and so on..
so next number= 2*46+2=94..
A
Question: What least number must be added to 1056, so that the sum is completely divisible by 23 ?
A.23
B.24
C.12
D.2
Answer: D.2
Explanation: 23) 1056 (45
92
---
136
115
---
21
---
Required number = (23 - 21)
= 2
ANSWER D
Question: A cricketer has a certain average for 10 innings. In the eleventh inning, he scored 108 runs, there by increasing his average by 6 runs. His new average is:
A.46
B.50
C.52
D.54
Answer: A.46
Explanation: Let average for 10 innings be x. Then,
(10x + 108)/11 = x + 6
= 11x + 66 = 10x + 108
= x = 42.
New average = (x + 6) = 48 runs.
ANSWER A
Question: How many three letter words are formed using the letters of the word THREE?
A.A)117
B.B)118
C.C)119
D.D)120
Answer: D.D)120
Explanation: The number of letters in the given word is five.
The number of three letter words that can be formed using these four letters is 5P4
= 5 * 4 * 3*2 = 120.
Answer:D
Question: In a pair of fractions, fraction A is twice the fraction B and the product of two fractions is 2/25. What is the value of fraction A?
A.1/5
B.1/25
C.2/5
D.Data inadequate
Answer: C.2/5
Explanation: A = 2B => B = 1/2 A, so, AB = 2/25
1/2 A2 = 2/25
A2 = 4/25
A = 2/5
ANSWER:C
Question: The difference between compound and simple interest on a certain sum of money for 3 years at 6 2/3% p.a is Rs.184. Find the sum?
A.28882
B.27772
C.23123
D.Rs.13500
Answer: D.Rs.13500
Explanation: P = (184*106) / [6 2/3 * 6 2/3 *(300*6 2/3)]
P = 13500
Answer: D
Question: What is the maximum number Q of 27 cubic centimetre cubes that can fit in a rectangular box measuring 8 centimetre x 9 centimetre x 12 centimetre ?
A.36
B.32
C.24
D.21
Answer: C.24
Explanation: 27 cubic centimetre cubes gives side = 3cm
so if:
L*W*H is 9*12*8, then max. cube we can have are 3*4*2 = 24
L*W*H is 9*8*12, then max. cube we can have are 3*2*4 = 24
L*W*H is 12*8*9, then max. cube we can have are 4*2*3 = 24
L*W*H is 12*9*8, then max. cube we can have are 4*3*2 = 24
L*W*H is 8*12*9, then max. cube we can have are 2*4*3 = 24
L*W*H is 8*9*12, then max. cube we can have are 2*3*4 = 24
In all cases we get Q=24 cubes.
Ans. C
Question: In a can, there is a mixture of milk and water in the ratio 3:2. If the can is filled with an additional 6 liters of milk, the can would be full and the ratio of milk and water would become 2:1. Find the capacity of the can?
A.36
B.34
C.32
D.30
Answer: A.36
Explanation: Let C be the capacity of the can.
(3/5)*(C-6)+6=(2/3)*C
9C-54+90=10C
C=36
The answer is A.
Question: The volumes of two cones are in the ratio 1 : 10 and the radii of the cones are in the ratio of 1 : 2. What is the length of the wire?
A.2:5
B.2:8
C.2:4
D.2:1
Answer: A.2:5
Explanation: The volume of the cone = (1/3)πr2h
Only radius (r) and height (h) are varying.
Hence, (1/3)π may be ignored.
V1/V2 = r12h1/r22h2 => 1/10 = (1)2h1/(2)2h2
=> h1/h2 = 2/5
i.e. h1 : h2 = 2:5
Answer: A
Question: To mail a package, the rate is 40 cents for the first pound and 5 cents for each additional pound. Two packages weighing 4 pounds and 6 pounds, respectively can be mailed seperately or combined as one package. Which method is cheaper and how much money is saved?
A.Combined, with a saving of 20 cents
B.Combined, with a saving of 35 cents
C.Separately, with a saving of 5 cents
D.Separately, with a saving of 15 cents
Answer: B.Combined, with a saving of 35 cents
Explanation: 4 pounds cost = 40+3*5 = 55
6 pounds cost = 40+5*5 = 65
Total = 120
10 pounds cost = 40+ 9*5 =85 dif. 35
Answer : B
Question: Twenty eight years ago,a father was three times as old as his son.Now the father is only twice as old as his son. Then the sum of the present ages of the son and the father is :
A.120
B.176
C.168
D.105
Answer: C.168
Explanation: Let the present ages of the father and son be 2x and x years respectively.
then,(2x-28)=3 (x-28)
x=56.
Required sum =(2x+x)=3x=168 years.
Answer is C
Question: In an election between two candidates A and B, the number of valid votes received by A exceeds those received by B by 15% of the total number of votes polled. If 20% of the votes polled were invalid and a total of 8720 votes were polled, then how many valid votes did B get?
A.1888
B.2999
C.2834
D.2777
Answer: C.2834
Explanation: Let the total number of votes polled in the election be 100k.
Number of valid votes = 100k - 20% (100k) = 80k
Let the number of votes polled in favour of A and B be a and b respectively.
a - b = 15% (100k) => a = b + 15k
=> a + b = b + 15k + b
Now, 2b + 15k = 80k and hence b = 32.5k
It is given that 100k = 8720
32.5k = 32.5k/100k * 8720 = 2834
The number of valid votes polled in favour of B is 2834.
Answer: C
Question: The probability that a brand A widget is defective is x, the probability that a brand B widget is defective is 0.06, and the probability that a brand C widget is defective is 0.04. There are 40 brand A widgets, 35 brand B widgets, 25 brand C widgets, and nothing else in a container. If a widget is selected at random from the container, the probability that the widget selected is defective is 0.053. What is the value of x?
A.0.05
B.0.055
C.0.07
D.0.1
Answer: B.0.055
Explanation: Given probability of defective items in each brand,
So, the number of items defective in brand A=x*40, in brand B=0.06*35 and brand C=0.04*25
Total number of widgets=40+35+25=100
the probability that the widget selected is defective is 0.053=(x*40+0.06*35+0.04*25)/100
=> 40x+2.1+1=5.3
=>40x = 2.2
>x=2.2/40=0.055
Ans B
Question: Rachel drove 40 1/4 kilometres in 45 minutes. What was her average rate of speed in kilometres per hour?
A.52
B.52 2/3
C.53
D.53 2/3
Answer: D.53 2/3
Explanation: D = 40(1/4) = 161/4
T = 3/4
S = D/T = 53 2/3
Answer = D
Question: What number must be added to 6, 16 and 8 to get an average of 13?
A.23
B.22
C.44
D.33
Answer: B.22
Explanation: B
22
Question: A box contains four silver coins, of which two coins have heads on both their faces, one coin has tail on both its faces and the fourth coin is a normal one. A coin is picked at random and then tossed. If head is the outcome of the toss, then find the probability that the other face (hidden face) of the coin tossed is also a head.
A.3/5
B.4/5
C.2/5
D.1/5
Answer: B.4/5
Explanation: There are four ways (2 heads in one two-headed coin and 2 heads in the other two-headed coin)
How many ways can you get heads from this entire set of coins? There are five ways (four as identified above and one from the normal coin)
Therefore probability = (number of ways to get heads from a two-headed coin)/(number of ways to get heads from any coin)
= 4/5
B
Question: There are 3 fictions and 6 non-fictions. How many cases are there such that 2 fictions and 2 non-fictions are selected from them?
A.90
B.120
C.45
D.180
Answer: C.45
Explanation: Number of ways of selecting 2 fiction books = 3C2
Number of ways of selecting 2 non fiction books = 6C2
3C2 * 6C2 = 3 * 15 = 45
Answer: C
Question: If the sum of two numbers is 22 and the sum of their squares is 404, then the product of the numbers is
A.40
B.44
C.80
D.88
Answer: A.40
Explanation: Sol.
Let the numbers be x and y.
Then, (x+y) = 22 and x2 + y2 = 404.
Now, 2xy = (x+y)2 - (x2 + y2)
= (22)2 - 404 = 484 - 404 = 80
xy = 40.
Answer A
Question: Worker A takes 10 hours to do a job. Worker B takes 15 hours to do the same job. How long it take both A & B, working together but independently, to do the same job?
A.40 days
B.40/9 days
C.39/9 days
D.6 days
Answer: D.6 days
Explanation: A's one hour work = 1/10.
B's one hour work = 1/15.
(A+B)'s one hour work = 1/10+1/15 = 5/30 = 1/6.
Both A & B can finish the work in 6 days
D
Question: A person can swim in still water at 4 km/h. If the speed of water 2 km/h, how many hours will the man take to swim back against the current for 6km?
A.3
B.6
C.8
D.7
Answer: A.3
Explanation: M = 4
S = 2
US = 4 - 2 = 2
D = 6
T = 6/2 = 3
Answer: A
Question: Find the invalid no.from the following series 15, 16, 34, 105, 425, 2124, 12756
A.16
B.34
C.105
D.425
Answer: D.425
Explanation: 2nd term = (1st term) * 1 + 1 = 15 *1 + 1 = 16.
3rd term = (2nd term) * 2 + 2 = 16 * 2 + 2 = 34
4th term = (3th term) *3 + 3 = 34 * 3 + 3 = 105
5th term = (4th term) * 4 + 4 = 105 * 4 + 4 = 424
6th term = (5th term) * 5 + 5 = 424 * 5 + 5 = 2125
5th term should 424 instead of 425.
D
Question: which number replaces the question mark and completes the puzzle ?
2 + 2 = 4
3 + 3 = 18
4 + 4 = 48
6 + 6= ?
A.135
B.150
C.185
D.180
Answer: D.180
Explanation: D
180
2 + 2 = 4 {2 * 2 * 1}
3 + 3 = 18 {3 * 3 * 2}
4 + 4 = 48 {4 * 4 * 3}
6 + 6 = 180 {6 * 6 * 5}
Question: What is the are of an equilateral triangle of side 16 cm?
A.64√8 cm2
B.64√2 cm2
C.62√3 cm2
D.64√3 cm2
Answer: D.64√3 cm2
Explanation: Area of an equilateral triangle
= √3/4 S2
If S = 16, Area of triangle
= √3/4 * 16 * 16
= 64√3 cm2;
Answer: D
Question: If m/63 is an integer, then each of the following must be an integer EXCEPT
A.4
B.3
C.5
D.11/2
Answer: D.11/2
Explanation: Now plug m =63 into the answer choices:
A. (63- 28)/7 =5. This is an integer
B. (63+ 21)/7 = 12. This is an integer
C. 14(63)/98 = 9. This is an integer
D. (63^2 - 49)/49 =80. This is an integer
E. (63+ 14)/14 = 11/2. This is NOT an integer
Answer: D