RikoteMaster/aqua-rat-mcqa huggingface dataset:
Question: Based on this year's costs, a company budgets P dollars for hiring N new employees next year. If the average cost of hiring each employee were to decrease 20% from this year's cost, then the greatest number of employees could hire next year using P dollars would be:
A.Equal to N
B.25% greater than N
C.20% greater than N
D.25% less than N
Answer: B.25% greater than N
Explanation: Correct answer is (B).
This year, the price of an employee is price1=P/N.
If this price decreases by 20% it becomes Price2=P/N*0.8
Then with P dollars, you can hire P/Price2 employees i.e. P/(P/N*0.8) i.e. N/1.1 i.e. 1.25*N
Which is 25% greater than N.
Question: There are a total of 15 numbers with an average of 11. The average of first seven numbers is 14 and the average of last seven numbers is 6. What is the middle number?
A.31
B.24
C.29
D.25
Answer: D.25
Explanation: The total of 15 numbers = 15X11 = 165
The total of first 7 and last 7 numbers is = 7 X 14+7 X 6 = 140
So, the middle number is (165 - 140 ) = 25
D
Question: (X^n - A^n) is completely divisible by (X - A), when
A.n is any natural number
B.n is an even natural number
C.n is an odd natural number
D.n is prime
Answer: A.n is any natural number
Explanation: For every natural number n, (X^n - A^n) is always divisible by (X - A)
Answer A.
Question: The average age of a group of n people is 15 years old. One more person aged 35 joins the group and the new average is 17 years old. What is the value of n?
A.8
B.9
C.10
D.11
Answer: B.9
Explanation: 15n + 35 = 17(n+1)
2n = 18
n = 9
The answer is B.
Question: Can you please walk me through how to best approach this problem? Thanks
If #p# = ap^3+ bp – 1 where a and b are constants, and #-4# = 2, what is the value of #4#?
A.-4
B.0
C.-2
D.-3
Answer: A.-4
Explanation: #p# = ap^3 + bp - 1
#-4# = 2
putting p = -4 in above equation
-64a -(4b +1) = 2 or
#-4# = (64a+4b+1) = -2
therefore 64a+4b = -3 .....(1
now putting p = 4
#4# = 64 a+4b - 1
using equation 1(64a+4b = -3)
#4# = -3-1 = -4
hence A
Question: A, B and C invested Rs.6600, Rs.4400 and Rs.11000 respectively, in a partnership business. Find the share of A in profit of Rs.12100 after a year?
A.Rs.3300
B.Rs.3100
C.Rs.3500
D.Rs.4200
Answer: A.Rs.3300
Explanation: 6600:4400:11000
3:2:5
3/10 * 11000
= Rs.3300
AnswerA
Question: In an election between two candidates, 20% of votes are were declares invalid. First candidate got 480 votes which were 60% of the total valid votes . The total number of votes enrolled in that election was:
A.2000 votes
B.2500 votes
C.3000 votes
D.4000 votes
Answer: C.3000 votes
Explanation: Answer: Option 'B'
(100%-20%=80%
48%-32%=16%
16% = 16×30 = 480
100% =100×30 =3000 votes)
C
Question: A train is 460 meter long is running at a speed of 45 km/hour. In what time will it pass a bridge of 140 meter length
A.20 seconds
B.30 seconds
C.40 seconds
D.48 seconds
Answer: D.48 seconds
Explanation: Explanation:
Speed = 45 Km/hr = 45*(5/18) m/sec
= 25/2 m/sec
Total distance = 460+140 = 600 meter
Time = Distance/speed
=600∗2/25=48seconds
Option D
Question: (x + 6) is a factor in x^2 - mx - 42. What is the value of m?
A.2
B.2.2
C.1
D.4
Answer: C.1
Explanation: I solved the second degree equation and found it like this:
x^2 - mx - 42 = 0
(x-7)(x+6) = 0
x=7 or x= -6
Substituting both values for x in the equation we find:
x^2 - mx -42
=> (-6)^2 - m(-6) = 42
=> 36+ 6m= 42
=> 6m = 42-36=6
=> m = 1
And with 7, using a similar process we end up with:
(7)^2 - m(7) =42
-7m = 42-49= -7
m=-1
Ao,ANS C
Question: A, B and C invested Rs.6300, Rs.4200 and Rs.10500 respectively, in a partnership business. Find the share of A in profit of Rs.12100 after a year?
A.3630
B.2890
C.2707
D.2700
Answer: A.3630
Explanation: 6300:4200:10500
3:2:5
3/10 * 12100
= 3630
Answer:A
Question: How many 1 1/4 foot pieces of cable can be cut out of a piece that is 30 feet long?
A.a.10
B.b.16
C.c.17
D.d.24
Answer: D.d.24
Explanation: Pretty Simple..the answer is choice (D) 24.
All that one has to do is :
1: Convert 1 1/4 into an improper fraction (5/4) or a decimal (1.25)
2: Divide 30 by 5/4 (or 1.25)
Answer =24 (D)
Question: In how many ways can 4 black and 5 white chess pieces be arranged in a row such that they occupy alternate places? Assume that the pieces are distinct.
A.20
B.1440
C.120
D.2880
Answer: D.2880
Explanation: 4 black chess pieces can be arranged in 4! ways and 5 white pieces can be arranged in 5 ! ways.
W_W_W_W
Number of ways = 4!*5! = 24 * 120 = 2880
Answer D
Question: If an integer x is to be selected at random from 1 to 200, inclusive, what is probability x(x+1) will be divisible by 4?
A.0.5
B.1
C.0.25
D.0.75
Answer: A.0.5
Explanation: because x(x+1) is always an even product of even*odd or odd*even factors,
there is a probability of 1 that that it will be divisible by 2,
and, thus, a probability of 1/2 that it will be divisible by 4
1*1/2=1/2 =0.5
Answer : A
Question: To be undaunted is to be impervious, undisturbed and ‘fearless’.
A.2
B.HH
C.28
D.28J
Answer: D.28J
Explanation: Answer:D
Question: In a company, 50 percent of the employees are men. If 60 percent of the employees are unionized and 70 percent of these are men, what percent of the non-union employees are women?
A.85%
B.80%
C.75%
D.70%
Answer: B.80%
Explanation: The percent of employees who are unionized and men is 0.7*0.6 = 42%
The percent of employees who are unionized and women is 60 - 42 = 18%
50% of all employees are women, so non-union women are 50%-18% = 32%
40% of all employees are non-union.
The percent of non-union employees who are women is 32%/40% = 80%
The answer is B.
Question: a right triangle has three sides (F, G, H). If F=5, G=8.66, and H=10, which angle is 90 degrees
A.FG
B.HG
C.HF
D.n/a
Answer: A.FG
Explanation: A) the angle FG is a right angle. HF, and HG are acute.
Question: A positive number x is multiplied by 5, and this product is then divided by 3. If the positive square root of the result of these two operations equals x, what is the value of x ?
A. 9/4
B. 3/2
C. 4/3
D. 5/3
Answer: D. 5/3
Explanation: sq rt(5x/3) = x
=> 5x/3 = x^2
=> x = 5/3
Ans - D
Question: Students in Class I and II of a school are in the ratio of 3 : 5. Had 15 students leave the school from each class, the ratio would have become 1 : 2. How many total students were there in the beginning?
A.120
B.64
C.96
D.80
Answer: A.120
Explanation: class 1 have 3x student and class 2 have 5x student.
3x-15/5x-15=1/2,6x-30=5x-15,x=15
45+75=120 student
answer A
Question: The maximum number of students among them 848 pens and 630 pencils can be distributed in such a way that each student get the same number of pens and same number of pencils?
A.10
B.4
C.2
D.14
Answer: C.2
Explanation: number of pens = 848
number of pencils = 630
Required number of students = H.C.F. of 848 and 630 = 2
Answer is C
Question: The average monthly salary of 8 workers and one supervisor in a factory was 430.@SSWhen@SSthe@SSsupervisor@CC@SSwhose@SSsalary@SSwas@SS430.@SSWhen@SSthe@SSsupervisor@CC@SSwhose@SSsalary@SSwas@SS430.Whenthesupervisor,whosesalarywas430. When the supervisor, whose salary was 870 per month, retired, a new person was appointed and then the average salary of 9 people was $$390 per month. The salary of the new supervisor is:
A.233
B.600
C.510
D.771
Answer: C.510
Explanation: Explanation:
Total salary of 8 workers and supervisor together = 9 Ã— 430 = 3870
Now total salary of 8 workers = 3870 âˆ’ 870 = 3000
Total salary of 9 workers including the new supervisor = 9 Ã— 390 = 3510
Salary of the new supervisor = 3510 âˆ’ 3000 = 510
Answer: C
Question: How long will a boy take to run round a square field of side 35 meters, If he runs at the rate of 9 km/hr?
A.22
B.38
C.37
D.56
Answer: D.56
Explanation: Answer: D) 56 sec
Question: 12 spheres of the same size are made from melting a solid cylinder of 8 cm diameter and 1 cm height. What is the diameter of each sphere?
A.2 cm
B.4 cm
C.8 cm
D.10 cm
Answer: A.2 cm
Explanation: Volume of cylinder = pi*r^2*h
Volume of a sphere = 4*pi*R^3 / 3
12*4*pi*R^3 / 3 = pi*r^2*h
R^3 = r^2*h / 16 = 1 cm^3
R = 1 cm
D = 2 cm
The answer is A.
Question: A small company is planning to rent either computer A or computer B to print customer mailing lists. Both computer A and computer B must be rented on an hourly basis. The rental fee is based only on the amount of time the computer is turned on. It will cost 40 percent more per hour to rent computer A than to rent computer B. Computer B would, however, require 20 hours more than computer A to do the job. If either computer A, or computer B were rented the total cost to rent the computer would be $850.00. What would be the approximate hourly charge to rent computer B?
A.$9.40
B.$11.30
C.$12.14
D.$17.80
Answer: C.$12.14
Explanation: Pa = price of A
Pb = price of B
Ta = time for A to complete the job
Tb = time for B to complete the job
Given
Pa = 1.4 Pb
Ta+20 = Tb
Pa*Ta = Pb*Tb=850
1.4Pb * (Tb-20) = Pb*Tb
1.4 Pb Tb - Pb Tb = 1.4 Pb * 20
0.4PbTb = 28Pb
Tb = 28/0.4 = 70
Pb=850/70 ~ 12.14
C
Question: The owner of a furniture shop charges his customer 60% more than the cost price. If a customer paid Rs. 2000 for a computer table, then what was the cost price of the computer table?
A.2789
B.2772
C.1250
D.6725
Answer: C.1250
Explanation: CP = SP * (100/(100 + profit%))
= 1250(100/160) = Rs. 1250.
Answer: C
Question: Tom spent six lucky days in Las Vegas. On his first day he won a net amount of only $20, but on each of the following days, the daily net amount he won grew by d dollars. If Tom won a total net amount of $1620 during his stay in Las Vegas, how much did he win on the last day?
A.330
B.500
C.520
D.540
Answer: C.520
Explanation: I drew a diagram:
1 - $20
2 -
3 -
4 - $320
5 -
6 -
Total: $1,620
Between 1 and 6 are 5 days where he won $1,600. This means he averaged $320 per day (1600/5). You can put $320 by 4 because it's the middle number. Now you just find the two points betwenn $20 and $320 (320-20 = 300 / 3 = 100). So each day, he earned $100 more. This means on day 6, tom earned$520. Answer choice C.
Question: The average of first nine prime numbers which are odd is?
A.16.1
B.15.1
C.14.1
D.17.1
Answer: C.14.1
Explanation: Explanation:
Sum of first 9 prime no. which are odd = 158
Average = 127/9 = 14.1
Answer:C
Question: If two sides of a triangle are 12 and 6, which of the following could be the area of triangle?
1. 35
2. 48
3. 56
A.a) 1 only
B.b) 1 and 2 only
C.c) 1 and 3 only
D.d) 2 and 3 only
Answer: D.d) 2 and 3 only
Explanation: when two sides of a triangle are known , the maximum area occurs when the angle between those two sides is 90.
lets say base = 12 , height =8 (angle = 90)
maximum area = (1/2)*12*8 = 48 ( this is the same maximum area even when base is 8 and height is 12).
if we fix the base and keep lowering the angle, it will result in a lower height . hence the resulting area will always be < 48.
C,D and E are ruled out.
3 and 2 are possible areas as their areas are less than 48.
Hence the answer is D.
Question: An error 2% in excess is made while measuring the side of a square. What is the percentage of error in the calculated area of the square?
A.4.05%
B.4.02%
C.4%
D.3%
Answer: A.4.05%
Explanation: Percentage error in calculated area
=(2+2+(2×2)/100)%
=4.04%
ANSWER:A
Question: Joan and Karl each bought a bicycle and the sum of their purchases was $800. If twice of what Joan paid was $40 more than what Karl paid, what did Joan pay for her bicycle?
A.$280
B.$300
C.$320
D.$340
Answer: A.$280
Explanation: J+K=800 so K=800-J
2J=K+40
2J=(800-J)+40
3J=840
J=280
The answer is A.
Question: When positive integer n is divided by 3, the remainder is 1. When n is divided by 7, the remainder is 5. What is the smallest positive integer k such that k+n is a multiple of 21?
A.2
B.4
C.6
D.8
Answer: A.2
Explanation: n = 3p + 1 = 7q + 5
n+2 = 3p + 3 = 7q + 7
n+2 is a multiple of 3 and 7, so it is a multiple of 21.
The answer is A.
Question: In an election between two candidates, one got 55% of the total valid votes, 20% of the votes were invalid. If the total number of votes was 7500, the number of valid votes that the other candidate got, was :
A.2500
B.2600
C.2700
D.2900
Answer: C.2700
Explanation: Total number of votes = 7500
Given that 20% of Percentage votes were invalid
Valid votes = 80%
Total valid votes = 7500x (80/100)
1st candidate got 55% of the total valid votes.
Hence the 2nd candidate should have got 45% of the total valid votes
Valid votes that 2nd candidate got = total valid votes x 45/100
7500x (80/100)x45/100= 2700
answer :C
Question: Which of the following equivalent to (1/125)^2?
A.(0.03)^5
B.(0.04)^3
C.(0.05)^6
D.(0.06)^3
Answer: B.(0.04)^3
Explanation: (1/125)^2 = (1/5^3)^2 = (1/5)^6 = (1/25)^3 = (0.04)^3
Answer: Option B
Question: There are 7 magazines lying on a table; 3 are fashion magazines and the other 4 are sports magazines. If 3 magazines are to be selected at random from the 8 magazines, what is the probability that at least one of the fashion magazines will be selected?
A.1/2
B.7/8
C.32/35
D.11/12
Answer: B.7/8
Explanation: answer isB
Total probability=7C3=48
4C3 +4C2*4C1+4C1*4C2=4+24+24=42
therefore the probability that at least one of the fashion magazines will be selected= 42/48=7/8
B
Question: if x/4-x-3/6=1,then find the value of x.
A.6
B.4
C.5
D.1
Answer: A.6
Explanation: (x /4)-((x-3)/6)=1=> (3x-2(x-3) )/12 = 1 => 3x-2x+6=12 => x=6.
Answer is A
Question: Triathlete Dan runs along a 2-mile stretch of river and then swims back along the same route. If Dan runs at a rate of 8 miles per hour and swims at a rate of 6 miles per hour, what is his average rate for the entire trip in miles per minute?
A.1/9
B.2/15
C.3/15
D.1/4
Answer: A.1/9
Explanation: Dan travels 4 miles round trip.
Running part: (2/8 = 1/4*60 = 15 minutes)
Swimming Part: (2/6 = 1/3*60 = 20 minutes)
4 miles in (15+20) minutes
4/35 = 1/9 mile per minute
Answer: 1/9 mile per minute
Question: A man has only 20-paise and 25-paise coins in a bag. If he has 50 coins in all totaling to Rs.11.25, then the number of 20-paise coins is
A.28
B.27
C.26
D.25
Answer: D.25
Explanation: x=20p;y=25p;
x+y=50;
0.20x+0.25y=11.25;
25x+25y=1250;
20x+25y=1125;
=>x=25;
ANSWER:D
Question: A takes twice as much time as B or thrice as much time to finish a piece of work. Working together, they can finish the work in 2days. B can do the work alone in?
A.8
B.10
C.12
D.15
Answer: C.12
Explanation: Suppose A,B,C takes x,x/2,x/3 hours to finish the work
Then, 1/x + 2/x + 3/x = 1/2
6/x = 1/2
x = 12
Answer is C
Question: The cost of 2 books and 2 magazines is $26. The cost of 1 book and 3 magazines is $27. How much does 1 magazine cost?
A.8
B.5
C.7
D.4
Answer: C.7
Explanation: Let the cost of 1 book = x, let the cost of 1 magazine = y
2x + 2y = 26
x = (26 - 2y)/2
x = 13 - y
Again,
(13 - y) + 3y = 27
13 + 2y = 27
2y = 14
y = 7
Answer: C
Question: If 45-[28-{37-(15-*)}]= 57, then * is equal to:
A.-29
B.-19
C.18
D.29
Answer: C.18
Explanation: 45-[28-{37-(15-*)}]= 57 => 45-[28-{37-15+*}]=57
45-[28-37+15-*]=57 => 45[43-37-*]=57
45-[6-*]=57 => 45-6+*=57
39+*=57 => *=57-39
= 18
ANSWER:C
Question: Five different books (A, B, C, D and E) are to be arranged on a shelf. Books C,D and E are to be arranged first and second starting from the right of the shelf. The number of different orders in which books A, B and may be arranged is
A.1!
B.2!
C.5!
D.15!
Answer: B.2!
Explanation: Solution
Since books C,D and E are arranged first and second, only books A and B will change order. Therefore it an arrangement problem involving 2 items and the number of different order is given by
2!
Answer B
Question: A line has a slope of 3/4 and intersects the point R (-12, -39). At which point does this line intersect the x-axis?
A.(40,0)
B.(30,0)
C.(0,40)
D.(40,30)
Answer: A.(40,0)
Explanation: Assume that the equation of the line is y=mx+c, where m and c are the slope and y-intercept.
You are also given that the line crosses the point (-12,-39), this means that this point will also lie on the line above.
Thus you get -39=m*(-12)+c , with m=3/4 as the slope is given to be 3/4.
After substituting the above values, you get c = -30.
Thus the equation of the line is y=0.75*x-30 and the point where it will intersect the x-axis will be with y coordinate = 0.
Put y=0 in the above equation of the line and you will get, x=40.
Thus, the point R of intersection is (40,0).
A is the correct answer.
Question: A and B enter into partnership with capital as 7:9. At the end of 8 months, A withdraws. If they receive the profits in the ratio of 8:9 find how long B's capital was used?
A.8
B.4
C.5
D.7
Answer: D.7
Explanation: 7 * 8 : 9 * x = 8:9 => x= 7
Answer:D
Question: A pipe can fill a cistern in 20 minutes whereas the cistern when fill can be emptied by a leak in 28 minutes. When both pipes are opened, find when the cistern will be full?
A.27
B.76
C.70
D.21
Answer: C.70
Explanation: 1/20 - 1/28 = 1/70
70 minutes.Answer: C
Question: A and B start a business with Rs.2000 and Rs.8000 respectively. How should they share their profits at the end of one year?
A.3:5
B.1:4
C.3:1
D.3:2
Answer: B.1:4
Explanation: They should share the profits in the ratio of their investments.
The ratio of the investments made by A and B =
2000 : 8000 => 1:4
Answer:B
Question: Find the sum to 200 terms of the series 1 + 4 + 6 + 5 + 11 + 6 + ....
A.30,200
B.29,800
C.30,400
D.40,400
Answer: A.30,200
Explanation: Spot the above series is a combination of two APs.
The 1st AP is (1 + 6 + 11 + ....) and the 2nd AP is (4 + 5 + 6 + ...)
Since the terms of the two series alternate
S =(1 + 6 + 11 + .... to 100 terms) + (4 + 5 + 6 + .... to 100 terms)
=> 100[2 x 1 + 99 x 5]/2 + 100[2 x 4 + 99 x 1]/2 --->(Using the formula for the sum of an AP)
=>50[497 + 107] =50[604] = 30200
Alternatively, we can treat every two consecutive terms as one.
So, we will have a total of 100 terms of the nature:
(1 + 4) + (6 + 5) + (11 + 6).... -> 5, 11, 17,....
Now, a= 5, d=6 and n=100
Hence the sum of the given series is
S= 100/2 x[2 x 5 + 99 x 6]
=> 50[604]
=> 30200
ANSWER:A
Question: P is five times as old as Q, and Q is seven years older than R. If R is z years old, what is P’s age in terms of z?
A.5z + 7
B.5z − 35
C.5z + 35
D.(z + 7)/5
Answer: C.5z + 35
Explanation: P = 5Q
Q = R+7 = z+7
P = 5(z+7) = 5z + 35
The answer is C.
Question: A certain roller coaster ride has between 29 and 150 people waiting in line to board. If riders are let on only in groups of 5 there will be 2 riders that do not get on. If the riders are let on only in groups of 6 all riders will be able to get on. Which of the following is the sum of the greatest possible number of people in the line and the least possible number of people in the line?
A.269
B.184
C.174
D.169
Answer: C.174
Explanation: Let x be the number of people
x=5m+2
x=6n
x=30p+12
Least = 30+12= 42
Highest = 30*4+12 = 132
Total = 174
ANSWER:C
Question: If money is invested at r percent interest, compounded annually, the amount of the investment will double in approximately 54/r years. If Joe's parents invested $5,000 in a long-term bond that pays 6 percent interest, compounded annually, what will be the approximate total amount of the investment 18 years later, when Joe is ready for college?
A. $20000
B. $15000
C. $12000
D. $10000
Answer: D. $10000
Explanation: Since investment doubles in 54/r years, then for r=6 it'll double in 54/6=~9 years (we are not asked about the exact amount so such an approximation will do). Thus after 18 years investment will become $5,000*2=$10,000 .
Answer: D.
Question: A pair of articles was bought for $50 at a discount of 60%. What must be the marked price of each of the article?
A.$25
B.$10
C.$29.65
D.$35.95
Answer: B.$10
Explanation: S.P. of each of the article = 50/2 = $25
Let M.P = $x
40% of x = 25
x = 25*.4 =$10
Answer is B
Question: If APPLE is coded as 0 and FLOWER is coded as 63, then BASKET is coded as
A.2
B.19
C.35
D.40
Answer: D.40
Explanation: APPLE = 1+16+16+12+5=50 i.e 5*0=0
FLOWER = 6+12+15+23+5+18=79 i.e 7*9=63
BASKET =2+1+19+11+5+20=58 5*8=40
ANSWER:D
Question: Annie will be half as old as Larry in 3 years. Annie will also be one-third as old as Jerome in 5 years. If Jerome is 12 years older than Larry, how old is Annie?
A.5
B.8
C.19
D.26
Answer: A.5
Explanation: J = L+12
(1) 2(A+3) = L+3
(2) 3(A+5) = J+5 = L+17
Let's subtract equation (1) from equation (2)
A+9 = 14
A = 5
The answer is A.
Question: Barbara has 8 shirts and 9 pants. How many clothing combinations does Barbara have, if she doesn’t wear 2 specific shirts with 3 specific pants?
A.41
B.66
C.36
D.70
Answer: B.66
Explanation: 8 shirts
9 pants
we can combine 2 shirts with (9-3) pants
2*6=12
we can combine the other shirts (6) with any pants (9)
6*9=54
Thus total :12+54=66	ANS:B
Question: 4,25,49,121,169,
A.149
B.169
C.289
D.209
Answer: C.289
Explanation: 17^2= 289 because follow sequence of square of the prime numbers
ANSWER:C
Question: When 1/10 percent of 4,000 is subtracted from 1/10 of 4,000, the difference is
A.396
B.36
C.3996
D.40
Answer: A.396
Explanation: (1/10)*4000 - (1/10)%*4000 =
400 - (1/1000)*4000 =
400 - 4 = 396
The answer is A.
Question: A river 3m deep and 36 m wide is flowing at the rate of 2 kmph the amount of water that runs into the sea per minute is?
A.4500
B.2678
C.3600
D.3400
Answer: C.3600
Explanation: (2000 * 3 * 36)/60
= 3600 M3
Answer:C
Question: Rates for having a manuscript typed at a certain typing service are $6 per page for the first time a page is typed and $4 per page each time a page is revised. If a certain manuscript has 100 pages, of which 35 were revised only once, 15 were revised twice, and the rest required no revisions, what was the total cost of having the manuscript typed?
A.$860
B.$850
C.$840
D.$830
Answer: A.$860
Explanation: 50 pages typed 1x
35 pages typed 2x (original + one revision)
15 pages typed 3x (original + two revisions)
50(6)+35(6+4)+15(6+4+4)=300+350+210=860
Answer - A
Question: A can do a piece of work in 20 days and B can do it in 15 days and C can do it 20 days. They started the work together and A leaves after 2 days and B leaves after 4 days from the beginning. How long will work lost?
A.10 2/5
B.10 2/0
C.12 2/3
D.10 2/1
Answer: C.12 2/3
Explanation: 2/20 + 4/15 + x/20 = 1
x = 38/3 = 12 2/3 Answer: C
Question: At the start of an experiment, a certain population consisted of 3 animals. At the end of each month after the start of the experiment, the population size was double its size at the beginning of that month. Which of the following represents the population size at the end of 6 months?
A. 2^3
B. 3^2
C. 2(3^10)
D. 3(2^6)
Answer: D. 3(2^6)
Explanation: 3*2^n where n is the #of month --> 3*2^6 Answer (D)
Question: In a bag there are coins of 50 paisa, 25 paisa and one rupee in the proportion 5:6:2. If there are in all Rs.42, the number of 25 paisa coins is?
A.16
B.42
C.16
D.84
Answer: B.42
Explanation: 5x 6x 2x
50 25 100
250x + 150x + 200x = 4200
600x = 4200
x = 7 => 6x = 42
Answer: B
Question: The HCF of two numbers is 42 and the other two factors of their LCM are 11 and 12. What is the largest number.
A.462
B.450
C.480
D.504
Answer: D.504
Explanation: Explanation:
HCF of the two numbers = 42
HCF will be always a factor of LCM
42 is factor of LCM
other two factors are 11 & 12
Then the numbers are (42 11) and (42 x 12)
= 462 and 504
Answer: Option D
Question: What will be the percentage increase in the area of the cube's surface if each of the cube's edges grows by 20%?
A.33%
B.44%
C.55%
D.56%
Answer: B.44%
Explanation: The question is very easy. My logic is the following:
A surface = 6*a^2
After 20% increase A surface = 6* ((1.2a)^2) = 6*1.44*a^2
The increase in the surface area = (6*1.44*a^2 - 6*a^2)/6*a^2 = (6*a^2(1.44-1))/(6*a^2) = 1.44-1=0.44 = 44%
ANSWER:B
Question: there are 3 girls and 6 boys. how many kids are there?
A.10
B.19
C.20
D.9
Answer: D.9
Explanation: D