RikoteMaster/aqua-rat-mcqa huggingface dataset:
Question: 2 men and 3 women are lined up in a row. What is the number of cases where they stand with each other in turn? (The number of cases in which men (or women) do not stand next to each other)
A.12
B.15
C.18
D.21
Answer: A.12
Explanation: First arrange 3 women. 3 women can be arranged in 3 places in 3! ways. Now
W Blank W BlankW
we have to fill the two blanks with 2 men. We can arrange 2 persons in 2 places in 2! ways.
3! * 2! = 12 ways.
A is the answer
Question: Lerry, Michael, and Doug have five donuts to share. If any one of the men can be given any whole number of donuts from 0 to 5, in how many different ways can the donuts be distributed?
A. 21
B. 42
C. 120
D. 504
Answer: A. 21
Explanation: Lerry, Michael, and Doug have five donuts to share to get the answer, see how can we get sum5with 3 numbers.
1) 0,0,5 = 3 combinations or 3! /2!
2) 0,1,4 = 6 combinations or 3!
similarly
3) 0,2,3 = 6 combinations
4) 1,1,3 = 3 combination
5) 2,2,1 = 3 combination
total =21=A
Question: A painting crew painted 80 houses. They painted the first y houses at a rate of x houses per week. Then more painters arrived and everyone worked together to paint the remaining houses at a rate of 4.25x houses per week. How many weeks did it take to paint all 80 houses, in terms of x and y?
A.(320 - y)/(5x)
B.(y +210)/(5x)
C.5(80 - y)/(4x)
D.(y + 400)/(4x)
Answer: B.(y +210)/(5x)
Explanation: Ans B
Plug some numbers
Let y = 40 houses and x = 20
then they painted 20 houses per week
as painters were added to the group , the rate of the group increased to 4.25 x => 4.25 * 20 = 85 houses per week
total time they took = (40/20) + (40/85) = 2.5 weeks
Putting the values of x and y in equation B
(y +210)/(5x) = (40+210)/5*20 = 250/100 = 2.5
Question: A man goes from A to B at a speed of 20 kmph and comes back to A at a speed of 30 kmph. Find his average speed for the entire journey?
A.76 kmph
B.24 kmph
C.54 kmph
D.56 kmph
Answer: B.24 kmph
Explanation: Distance from A and B be 'd'
Average Speed
= total distance/total time
Average Speed
= (2d)/[(d/20) + (d/30)]
= (2d)/[5d/60)
=> 24 kmph.
Answer: B
Question: A box contains 100 balls, numbered from 1 to 100. If 3 balls are selected at random and with replacement from the box. If the 3 numbers on the balls selected contain two odd and one even. What is the probability Z that the first ball picked up is odd numbered?
A.	0
B.	1/3
C.	1/2
D.	2/3
Answer: D.	2/3
Explanation: Answer-D
Selecting the balls either Even or Odd is having probability 50/100=1/2
We have already selected 3 balls with 2 odd numbers and 1 even number.
So we have 3 combinations OOE, OEO, EOO. We have 3 outcomes and 2 are favourable as in 2 cases 1st number is odd. So probability Z is 2/3.D
Question: Two trains T1 and T2 start simultaneously from two stations X and Y respectively towards each other. If
they are 60 km apart both 3 and 6 hours after start, then find the distance between the two stations.
A.240 km
B.200 km
C.220km
D.180km
Answer: B.200 km
Explanation: In first 3 hours T1 travels R km and T2 travels S km.
After 6 hours they traveled R+S+60+ 60
2(R+S ) = R+S +120
R+S = 120
Hence distance between XY is R+S+ 60 = 120 +60 =200
Answer : B
Question: A boat can travel with a speed of 25km/hr in still water. If the speed of the stream is 5km/hr, find the time taken by the boat to go 90km downstream.
A.1 hr
B.2 hrs
C.3 hrs
D.4 hrs
Answer: C.3 hrs
Explanation: Speed downstream = (25 + 5) km/hr = 30 km/hr.
Time taken to travel 90 km downstream = 90/30 hrs = 3 hrs.
Answer : C
Question: An incredible punch is composed of mango, orange juice, and milk. How many pints of orange juice are required to make 9 gallons of punch containing twice as much mango as orange juice and three times as much orange juice as milk? (1 Gallon = 8 Pints )
A.13 pints
B.7.2 pints
C.5 pints
D.12 pints
Answer: B.7.2 pints
Explanation: 1 gallon=8 pints
9 gallons=72
mango=2 orange
orange=3 milk
mango+orange+milk=72
2 orange+orange+1/3 orange=72
10 orange=72
orange=7.2pints
Answer B
Question: If a man can cover 12 metres in 0ne second, how many kilometres can he cover in 3 hours 45 minutes?
A.132 km
B.167 km
C.143 km
D.162 kilometres
Answer: D.162 kilometres
Explanation: D
12 m/s = 12 * 18/5 kmph
3 hours 45 minutes = 3 3/4 hours = 15/4 hours
Distance = speed * time = 12 * 18/5 * 15/4 km = 162 km.
Question: John has on his shelf four books of poetry, two novels, and two reference works. Suppose from these ten books, we were to pick two books at random. What is the probability that we pick one novel and one reference work?
A.1/2
B.2/5
C.4/45
D.7/20
Answer: C.4/45
Explanation: When we are picking two books, one novel and one reference work, we could either pick a novel first and then a reference book or pick a reference book and then a novel. Therefore the answer is 2/10*2/9 + 2/10*2/9 = 4/45.
Answer: C
Question: A window 2 inches wide is placed on the back of a rectangular painted area with dimensions 8 inches by 12 inches. What is the area of the window, in square inches?
A.44
B.96
C.128
D.144
Answer: B.96
Explanation: This question is an example of a 'punch out' question - we have to find the area of EVERYTHING, then 'punch out' the part that we don't want.
We're told that a window 2 inches wide is placed around a rectangular painted area with dimensions 8 inches by 12 inches. We're asked for the area of the window, in square inches.
Area of a rectangle = (length)(width)
So the area of the window is... (8)(12) = 96
The window 'adds' 2 inches to the top, bottom, left and right 'sides' of the painted area, so the area of EVERYTHING is...
(8+2+2)(12+2+2) = (12)(16) = 196
When we 'punch out' the area of the painted area, we'll be left with the area of the window:
192 - 96 = 96
Final Answer:
B
Question: Two trains of equal length are running on parallel lines in the same direction at 46 km/hr and 36 km/hr. The faster train passes the slower train in 36 seconds. The length of each train is:
A.50 m
B.72 m
C.80 m
D.82 m
Answer: A.50 m
Explanation: Let the length of each train be x metres.
Then, distance covered = 2x metres.
Relative speed = (46 - 36) km/hr
(10 x (5/18) ) m/s = 25/9 m/s
2x/36 = 25/9
2x=100
x=50
ANSWER:A
Question: X and Y invest Rs.12500 and Rs.17500 respectively in a business. At the end of the year, they make a profit of Rs.26400. What is the share of X in the profit?
A.Rs.14400
B.Rs.26400
C.Rs.11000
D.Rs.12500
Answer: C.Rs.11000
Explanation: Ratio of the investment=12000:17500=5:7
Share of X in the profit=(26400×5)/12=11000
ANSWER:C
Question: The sum of the first 50 positive even integers is 2550. What is the sum of the even integers from 302 to 400 inclusive?
A.11,550
B.14,550
C.17,550
D.20,550
Answer: C.17,550
Explanation: 2 + 4 + 6 + 8 +...+ 100 = 2550
302 + 304 + ... + 400 = 50(300) + (2+4+...+100) = 15,000 + 2550 = 17,550
The answer is C.
Question: A train 225 m long passes a man, running at 10km/hr in the same direction in which the train is going, in10 seconds. The speed of the train is:
A.81
B.90
C.91
D.85
Answer: C.91
Explanation: Speed of the train relative to man =225/10 m/sec
=45/2m/sec.
=45/2x18/5km/hr
= 81 km/hr.
Let the speed of the train be x km/hr. Then, relative speed = (x - 5) km/hr.
x - 10 = 81 =91km/hr.
Answer:C
Question: A certain company assigns employees to offices in such a way that some of the offices can be empty and more than one employee can be assigned to an office. In how many ways can the company assign 3 employees to 4 different offices?
A.52
B.64
C.32
D.11
Answer: B.64
Explanation: Each of three employee can be assigned to either of offices, meaning that each has 2 choices --> 4*4*4=4^3=64.
Answer: B.
Question: It takes John exactly 30 minutes to rake a lawn and it takes his son Todd exactly 60 minutes to rake the same lawn. If John and Todd decide to rake the lawn together, and both work at the same rate that they did previously, how many minutes will it take them to rake the lawn
A.16
B.45
C.36
D.20
Answer: D.20
Explanation: 1)POE- John takes 30 min so if he takes help of someone else, it has to be less than 30 min..
only A and B are left..
if both do the work in 30 mis each, the combined time will be 15 mins, so 16 is slightly less when the other person does in 60 mins..
ans 20 D
Question: What will come in place of the x in the following Number series? 12, 38, 116, 350, x
A.1052
B.5464
C.3456
D.7554
Answer: A.1052
Explanation: 12
12 Ã— 3 + 2 = 38
38 Ã— 3 + 2 = 116
116 Ã— 3 + 2 = 350
350 Ã— 3 + 2 = 1052
A
Question: Machine A and machine G are each used to manufacture 660 sprockets. It takes machine A 10 hours longer to produce 660 sprockets than machine G. Machine G produces 10 percent more sprockets per hour than machine A. How many sprockets per hour does machine A produces?
A.6
B.6.6
C.60
D.100
Answer: A.6
Explanation: [Reveal]Spoiler:
TimeG: 660/x
TimeA: [660/x+10]
660/x = [660/x+10] *110/100
660/x =66*11/x+10
660x+10= 66*11*x
660x +6600 = 66*11*x
x= 100
plug in back to timeA
660/100+10 => 660/110 = 6
Question: 350 is increased by 50%. Find the final number.
A.725
B.625
C.225
D.525
Answer: D.525
Explanation: ExplanationFinal number = Initial number + 50%(original number) = 350 + 50%(350) = 350 + 175 = 525.Answer D
Question: If f(x) = 12 - x^2/2 and f(2k) = 5k, what is one possible value for k?
A.2
B.3
C.4
D.5
Answer: D.5
Explanation: First of all, see thisGMAT blog postand check the related lesson linked below for some background on function notation.
We can plug anything in for x and get a result. You can find f(1), for example, by plugging in 1 where x is, and you would get 12 - 1/2 = 11.5. Or we could find f(2), which would be 12 - 4/2 = 10.
So the notation f(2k) means that we are going to plug a 2k in for x everywhere in the formula for f(x). That would be:
f(2k) = 12 - (2k)^2/2 = 12 - 2k^2.
Remember that we have to square both the 2 and the k, to get 4k2. Now, this expression, the output, we will set equal to 2k.
12 - 2k^2 = 2k --> k = -3 or k =5.
All the answers are positive, so we choose k = 5.
Answer =D
Question: A card is drawn from a pack of 52 cards the probability of getting queen of club or aking of a heart?
A.8/58
B.9/25
C.1/26
D.6/25
Answer: C.1/26
Explanation: here n(s)=52
let E be the event of getting queen of the club or king of kings
n(E)=2
p(E)=n(E)/n(S)=2/52=1/26
Answer(C)
Question: A reduction of 40% in the price of oil enables a house wife to obtain 8 kgs more for Rs.2400, what is the reduced price for kg?
A.Rs.120
B.Rs.125
C.Rs.130
D.Rs.135
Answer: A.Rs.120
Explanation: Explanation:
2400*(40/100) = 960 ---- 8
? ---- 1 => Rs.120
Answer: A
Question: Eleven bags are bought for Rs.1000 and sold at 10 for Rs.1200. What is the gain or loss in percentage?
A.10%
B.22%
C.25%
D.20%
Answer: B.22%
Explanation: Explanation:
As selling price is Rs.1200 for 10 bags, each bag is sold at Rs.120.
Hence, the profit is Rs.100 after selling 10 bags plus the selling price of 1 bag = 100 + 120 = Rs.220.
%profit = 220/1000 *100
= 22%
ANSWER B
Question: I. x + 2y + 3z = 2
II. x + y - z = 0
III. 2x + 2y - z = 1
What is the value of y in the system above?
A. -2
B. -1
C. 0
D. 1
Answer: A. -2
Explanation: 1. from the given system of equations i can make equation II. to be x + y = z
2. now put that in III. :
2x + 2y - (x + y) = 1
= 2x + 2y - x - y = 1
= x + y = 1
that gives usz = 1!
3. put z = 1 in I. and solve:
x + 2y + 3 = 2; calculate minus 3
= x + 2y = -1; calculate minus x
=2y = -1 - x;
4. now put 2y = -1 - x in III. and solve:
2x + (-1 - x) - 1 = 1
= x - 2 = 1; calculate plus 2
that gives usx = 3
5. now solve for y with x = 3 and z = 1:
x + y = 1
= 3 + y = 1; calculate minus 3
that gives y = -2, and hence answer (A) -2
Question: Steve gets on the elevator at the 11th floor of a building and rides up at a rate of 47 floors per minute. At the same time Joyce gets on an elevator on the 51st floor of the same building and rides down at a rate of 53 floors per minute. If they continue traveling at these rates, at which floor will their paths cross?
A.19
B.28
C.30
D.33
Answer: D.33
Explanation: Steve gets on the elevator at the 11th floor of a building and rides up at a rate of 47 floors per minute. At the same time Joyce gets on an elevator on the 51st floor of the same building and rides down at a rate of 53 floors per minute. If they continue traveling at these rates, at which floor will their paths cross?
40 floors/100 floors per minute=2/5 minutes
11+57/3=33
51-63/3=33
Answer : D
Question: A tap can fill the tank in 15 minutes and another can empty it in 8 minutes. If the tank is already half full and both the taps are opened together, the tank will be:
A.filled in 12 min
B.emptied in 12 min
C.filled in 8 min
D.will be empty in 8 min
Answer: D.will be empty in 8 min
Explanation: work done by both taps= 1/15+(-1/8)= -7/120 so tank will be emptied becoz of minus sign.
so time taken= 120/7
given the tank is already half filled
so another half will be emptied in 120/7*1/2
nearly 8 minutes
ANSWER:D
Question: For my anniversary, I decided to surprise my wife. Since she is a voracious reader, I decided to collect a lot of books for her. On the first day of the month, I bought one book, on the second, I bought two and on the third, I bought three. This process went on till the anniversary and on the day, I had 231 books with me to gift her.
Can you calculate, on which day is our anniversary?
A.31
B.28
C.23
D.21
Answer: D.21
Explanation: D
21rd day
1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10 + 11 + 12 + 13 + 14 + 15 + 16 + 17 + 18 + 19 + 20 + 21 = 231
Thus our anniversary falls on the 21rd day of the month.
You can apply other formulas to shorten the process but that is the simplest way to do it.
Question: A company has two models of computers, model X and model Y. Operating at a constant rate, a model X computer can complete a certain task in 72 minutes and a model Y computer can complete the same task in 36 minutes. If the company used the same number of each model of computer to complete the task in 1 minute, how many model X computers were used?
A.22
B.23
C.24
D.25
Answer: C.24
Explanation: Let's say 1 work is processing 72 gb of data.
Model X : 1 gb per min
Model Y : 2 gb per min
Working together, 1 X and 1 Y = 3 gb per min
So, 24 times as many computers would work at 72 gb per min.
So no. of X =24
Answer is C
Question: Laura has a deck of standard playing cards with 13 of the 52 cards designated as a "heart." If Laura shuffles the deck thoroughly and then deals 10 cards off the top of the deck, what is the probability that the 10th card dealt is a heart?
A.1/4
B.1/5
C.5/26
D.12/42
Answer: A.1/4
Explanation: Desired outcomes= 13
Total outcomes= 52
Probability of getting any card as the heart card= 13/52= 1/4
And the same probability will be for 10th card as well.
A is the answer
Question: If P = Q-R, -1 < R < 0 and Q=0, which of the following is correct?
A.P < -1.
B.0 < P <2
C.P > 0
D.0 < P <4
Answer: C.P > 0
Explanation: Q is 0 & R is -ve
For min. value max. numerator and minimize denominator
take Q=0 & R=-0.9
P=0-(-0.9)
P > 0
Ans C
Question: Approximately what percentage of the world’s forested area is represented by Finland given that Finland has 53.42 million hectares of forested land of the world’s 8.076 billion hectares of forested land.
A.0.0066%
B.0.066%
C.0.66PERCENT
D.6.6%
Answer: C.0.66PERCENT
Explanation: Approximation is a strategy that helps us arrive at less than an exact number and the inclusion in this problem of the word “approximately” is an obvious clue. First, 8.076 billion is 8,076 million. Next, 8,076 million rounds to 8,000 million and 53.42 million rounds to 53 million. Dividing 53 million by 8,000 million we arrive at 0.0066 (53M/8,000M). We convert this decimal figure to a percentage by multiplying by 100 (or moving the decimal point two places to the right) and adding a percent sign in order to obtain our answer of 0.66%. Note that the shortcut method involves comparing 53 million to 1% of 8,000 million or 80 million. Since 53 million is approximately two-thirds of 80 million then the answer is some two-thirds of 1% or 0.66%.
Answer: C.
Question: If y = 2 + 2K and y≠0y≠0, then 2/y + 1/y + 1/y + 1/y = ?
A.1/(8+8k)
B.5/2(1+k)
C.1/(8+k)
D.4/(8+k)
Answer: B.5/2(1+k)
Explanation: 2/Y + 1/Y + 1/Y + 1/Y
= 5/Y
= 5/(2 + 2K)
= 5/2(1 + K)
ANSWER:B
Question: Two trains are running at 40 km/hr and 20 km/hr respectively in the same direction. Fast train completely passes a man sitting in the slower train in 5 sec. What is the length of the fast train?
A.27 7/9
B.27 7/6
C.27 7/2
D.27 7/9
Answer: D.27 7/9
Explanation: Relative speed = (40 - 20) = 20 km/hr.
= 20 * 5/ 18 = 50/9 m/sec.
Length of faster train = 50/9 * 5 = 250/9 = 27 7/9 m.
Answer:D
Question: P, Q, R enter into a partnership. P initially invests 25 lakh and adds another 10 lakh after one year. Q initially invests 35 lakh and withdraws 10 lakh after 2 years. R's investment is Rs 30 lakh. In what ratio should the profit be divided at the end of 3 years?
A.19:18:19
B.18:19:19
C.19:17:18
D.19:19:18
Answer: D.19:19:18
Explanation: P : Q : R
=(25×1+35×2):(35×2+25×1) :(30×3)
=95:95:90=19:19:18
Answer is D.
Question: The sale price of a trolley bag including the sale tax is Rs. 1232. The rate of sale tax is 10% . If the shopkeeper has made a profit of 12%, the cost price of the trolley bag is:
A.Rs 1000
B.Rs 1515
C.Rs 1525
D.Rs 1250
Answer: A.Rs 1000
Explanation: Explanation :
110% of S.P. = 1232
S.P. = Rs.(1232 x 100/110) = Rs.1120.
C.P. = Rs (100/112 x 1120) = Rs 1000
Answer : A
Question: Vishal and Raghu jointly started a business. Vishal invested three times as Raghu did and invested his money for double time as compared to Raghu. Raghu earned Rs. 4000. If the gain is proportional to the money invested and the time for which the money is invested then the total gain was ?
A.28,000
B.28,129
C.28,109
D.28,009
Answer: A.28,000
Explanation: Investments ratio is = 3:1
Time period ratio is = 2:1
As they are proportional to gain
------
Gain ratio of Vishal and raghu = 6:1
But given Raghu got Rs. 4000,
=? 1 ----- 4000
7 ----- ?
=> Rs.28,000
The total gain = Rs.28,000
Answer: A
Question: Suppose we have six marbles: 3 blue marbles, 2 red marbles, and one green marble. Suppose we are going to put them into three cups: a grey cup, a white cup, and a purple cup. We could put all six in any cup and leave two cups empty; or we could put marbles in two cups and leave one cup empty; or we could put some marbles in each of the three cups. How many combinations are possible?
A.150
B.160
C.200
D.180
Answer: D.180
Explanation: # ways to distribute Blue marbels(3) is :
1 in each cup= 1
2 in one cup and 1 in other=6
all 3 in one cup = 3
total 1+6+3=10 possibilities
# ways to distribute Red marbels(2) is :
1 in each cup = 3 ways
all in one cup = 3ways
total 6ways.
# ways to distribute Green marbels(1) is :
3 ways
total number of ways = 10*6 *3 = 180
D
Question: The diameter of two circles are 18 cm and 8 cm. The distance between their centres is 13 cm. What is the number of common tangents?
A.3
B.2
C.1
D.5
Answer: A.3
Explanation: A
3
Here, r1 = 9 cm and r 2 = 4 cm
r 1 + r 2 = 9 + 4 = 13 cm
and r 1 – r 2 = 9 – 4 = 5cm
Also, d = 13 cm
Here, d = r 1 + r 2
= 13 cm
Hence, two circles touch each other externally, so three total no of common tangents are three.
Question: It was Sunday on Jan 1, 2006. What was the day of the week Jan 1, 2010?
A.Sunday
B.Sarurday
C.Friday
D.Wednesday
Answer: C.Friday
Explanation: Explanation:
On 31st December, 2005 it was Saturday. Number of odd days from the year 2006 to the year 2009 = (1 + 1 + 2 + 1) = 5 days. On 31st December 2009, it was Thursday. Thus, on 1st Jan, 2010 it is Friday.
Answer: C
Question: The length of a train and that of a platform are equal. If with a speed of 90 k/hr, the train crosses the platform in one minute, then the length of the train (in meters) is?
A.752
B.799
C.719
D.750
Answer: D.750
Explanation: Speed = [90 * 5/18] m/sec = 25 m/sec; Time = 1 min. = 60 sec.
Let the length of the train and that of the platform be x meters.
Then, 2x/60 = 25 è x = 25 * 60 / 2 = 750
Answer: D
Question: A train running at the speed of 60 km/hr crosses a pole in 6 seconds. What is the length of the train?
A.100
B.130
C.150
D.170
Answer: A.100
Explanation: Speed=(60x5/18)m/sec = (50/3) m/sec.
Length of the train = (Speed x Time).
Length of the train = (50/3 x 6)m = 100 m.
Answer is A.
Question: Jackie has two solutions that are 2 percent sulfuric acid and 12 percent sulfuric acid by volume, respectively. If these solutions are mixed in appropriate quantities to produce 60 liters of a solution that is 10 percent sulfuric acid, approximately how many liters of the 12 percent solution will be required?
A.18
B.20
C.48
D.36
Answer: C.48
Explanation: let a=amount of 2% acid and b= amount of 12% acid.
Now, The equation translates to,
0.02a + .12b = .1(a+b)
but a+b= 60
therefore .02a + .12b = .1(60)
=> 2a + 12b = 600
but b=60-a
therefore
2a+ 12(60-a) = 600
=> 10a = 120
hence a = 12. b = 60 -12 = 48.
Answer : C
Question: If after successive discounts of 20% and 25/4% on the marked price of an article, a trader gets 20% profit on the cost price,then by what percent is the marked price above the cost price?
A.50%
B.60%
C.70%
D.80%
Answer: B.60%
Explanation: Let the market price be RS 100. Then after first discount S.P becomes 80 and after another discount it becomes Rs. 75.
so S.P = 75. now with this S.P he has made a profit of 20% and hence the
C.P = (75/120)*100 = 62.5
so percentage change with respect to market price is = (37.5/62.5)*100
giving 60%
ANSWER:B
Question: 4/9 × 6/3 + 11/27 – 18/81 = ?
A.27(5/24)
B.13 (2/7)
C.24 (5/27)
D.17 (3/21)
Answer: C.24 (5/27)
Explanation: Explanation:
= 4/9 × 6/3 + 11/27 – 18/81
=4/9 × 6/3 + 11/27 – 6/27
= 12*54+11-6/27 = 653/27 = 24 (5/27)
Answer: Option C
Question: When 30 is divided by the positive integer k, the remainder is 6, for how many different values of k is this true?
A.2
B.3
C.5
D.7
Answer: C.5
Explanation: When 30 is divided by k, remainder is 6 i.e. there are 6 balls leftover after grouping. so k must be greater than 6.
It also means that 30 is completely divisible by k.
Factors of 24 are 1, 2, 3, 4, 6, 8, 12, 24
Out of these, k can be 4, 6, 8, 12, 24.
Answer (C)
Question: A letter lock consists of three rings each marked with eight different letters. The number of distinct unsuccessful attempts to open the lock is at the most?
A.176
B.511
C.518
D.519
Answer: B.511
Explanation: Since each ring consists of eight different letters, the total number of attempts possible with the three rings is
= 8 * 8 * 8 = 512. Of these attempts, one of them is a successful attempt.
Maximum number of unsuccessful attempts
= 512 - 1 = 511.
Answer: B
Question: What least value should be replaced by * in 223*431 so the number become divisible by 9
A.3
B.4
C.5
D.6
Answer: A.3
Explanation: Explanation:
Trick: Number is divisible by 9, if sum of all digits is divisible by 9, so (2+2+3+*+4+3+1) = 15+* should be divisible by 9,
15+3 will be divisible by 9,
so that least number is 3.
Answer: Option A
Question: In a group of 5 boys and 5 girls, four children are to be selected. In how many different ways can they be selected such that at least one girl is included?
A.175
B.190
C.205
D.220
Answer: C.205
Explanation: The total number of ways to choose 4 children is 10C4 = 210
The number of ways to choose only boys is 5C4 = 5
The number of groups which include at least one girl is 205.
The answer is C.
Question: What is the sum of the integers from -194 to 195 inclusive?
A.0
B.5
C.195
D.875
Answer: C.195
Explanation: sum/n= average.
sum=(average)(n)
average=a+b/2=194+195/2=0.5
number of items(n)=B-A+1=195-(-194)+1=195+195=390.
sum=average*n=0.5*390=195.
answer is C
Question: If a man buys 10 lollipops for $80 and sold them for $2 dollars determine his loss.
A.50
B.60
C.70
D.80
Answer: B.60
Explanation: Cost of 10 lollipops = $80
Sold each lollipop for $2
So, he sold 10 lollipops for $(10 × 2) = $20
Loss = $(80 – 20) = $60
answer :B
Therefore, loss = $ 60.
Question: What is the tens' digit R of the sum of the first 40 terms of 1, 11, 111, 1111, 11111, 111111, ...?
A.R=2
B.R=3
C.R=4
D.8
Answer: B.R=3
Explanation: All of the first 40 terms have 1 at the units place.
Except the first term, the tens digit of all the remaining 39 terms is 1.
So now if you do the addition
1 1
1 1
. . .
. . .
. . .
1 1
0 1
3 0
Answer is B