RikoteMaster/aqua-rat-mcqa huggingface dataset:
Question: What will come in place of the x in the following Number series? 25, 100, x, 1600, 6400
A.6400
B.5600
C.5790
D.8554
Answer: A.6400
Explanation: (A)
25 x 4 = 100, 100 x 4 = 400, 400 x 4 = 1600, 1600 x 4 = 6400.
Question: At what price must an article costing Rs.47.50 be marked in order that after deducting 5% from the list price. It may be sold at a profit of 25% on the cost price?
A.62.5
B.62.1
C.62.9
D.62.2
Answer: A.62.5
Explanation: CP = 47.50
SP = 47.50*(125/100) = 59.375
MP*(95/100) = 59.375
MP = 62.5
Answer: A
Question: A grocer has a sale of Rs. 6435, Rs. 6927, Rs. 6855, Rs. 7230 and Rs. 6562 for 5 consecutive months. How much sale must he have in the sixth month so that he gets an average sale of Rs. 6500?
A.Rs. 4991
B.Rs. 5001
C.Rs. 5991
D.Rs. 6001
Answer: A.Rs. 4991
Explanation: Total sale for 5 months = Rs. (6435 + 6927 + 6855 + 7230 + 6562) = Rs. 34009.
Required sale = Rs. [ (6500 x 6) - 34009 ]
= Rs. (39000 - 34009)
= Rs. 4991.
answer :A
Question: Find the sum of divisors of 544 which are perfect squares
A.21
B.22
C.23
D.24
Answer: A.21
Explanation: perfect squares divisiors are 1, 2^2 & 2^4 only
sum of divisors of 544 which are perfect squares = 1 + 2^2 + 2^4 = 21
ANSWER:A
Question: Sushil got twice as many marks in English as in Science. His total marks in English, Science and Maths are 170. If the ratio of his marks in English and Maths is 5:3, find his marks in Science?
A.50
B.77
C.66
D.55
Answer: A.50
Explanation: S:E = 1:2
E:M = 5:3
------------
S:E:M = 5:10:6
5/17 * 170 = 50
Answer: A
Question: If f(y)=y^2 and y is a positive integer, which of the following CAN be the value of f(f(y))?
A.10
B.15
C.144
D.81
Answer: D.81
Explanation: f(y)=y^2
f(f(y)) = (y^2)^2
f(f(3) = (3^2)^2 = 81
Answer D
Question: A certain number when divided by 45 leaves a remainder 31, what is the remainder if the same number be divided by 15?
A.2
B.7
C.6
D.1
Answer: D.1
Explanation: Explanation:
45 + 31 = 76/15 = 1 (Remainder)
Answer: D
Question: A test has 180 questions. Each question has 5 options, but only 1 option is correct. If test-takers mark the correct option, they are awarded 1 point. However, if an answer is incorrectly marked, the test-taker loses 0.25 points. No points are awarded or deducted if a question is not attempted. A certain group of test-takers attempted different numbers of questions, but each test-taker still received the same net score of 40. What is the maximum possible number of such test-takers?
A.29
B.33
C.35
D.40
Answer: A.29
Explanation: A correct answers get you 1 point, an incorrect answer gets you MINUS 1/4 point and a skipped question gets you 0 points. Since there are 200 total questions, there are a variety of ways to get a total of 40 points.
Let C be the number of correct answers and let I be the number of incorrect answers.
To get 40 points, a test taker must have at least 40 correct answers. Then C=> 40.
For every correct question above 40, the test taker has 4 incorrect answers.
Then, the I = 4*(C - 40).
Also, I + C <= 180. Thus 5C <= 340 and so C <= 68.
Then 40 <= C <= 68 and C can have 29 possible values.
The answer is A.
Question: A train 240 m long passed a pole in 24 sec. How long will it take to pass a platform 650 m long?
A.870
B.89
C.90
D.97
Answer: B.89
Explanation: Speed = 240/24 = 10 m/sec.
Required time = (240 + 650)/10 = 89 sec.
Answer: Option B
Question: For a light that has an intensity of 60 candles at its source, the intensity in candles, S, of the light at a point d d feet from the source is given by the formula S=60k/d^2 60, where k is a constant. If the intensity of the light is 20 candles at a distance of 3 feet from the source, what is the intensity of the light at a distance of 30 feet from the source?
A.3/10 candles
B.1/2 candles
C.1 1/3 candles
D.1/5 candles
Answer: D.1/5 candles
Explanation: ANS = 3/10
S= 60k/d^2
At 3 feet
20 = 60k/9 so k = 3
At 20 feet
S = 60 *3/30^2 = 1/5
D
Question: The areas, in kilometers squared, of some countries are given below. USA: 9,629,091, Russia: 20,098,242, China: 9,598,094, Canada: 9,984,670, the UK: 242,400 and India: 3,287,263.
What is the difference between the areas of Russia and China?
A.5,476,811 kilometers squared
B.10,500,148 kilometers squared
C.9,843,123 kilometers squared
D.1,878,965 kilometers squared
Answer: B.10,500,148 kilometers squared
Explanation: he difference between the areas of Russia and China is given by
20,098,242 - 9,598,094 = 10,500,148 kilometers squared
correct answer B
Question: The true discount on Rs. 1760 due after a certain time at 12% per annum is Rs. 160. The time after which it is due is :
A.6 months
B.8 months
C.9 months
D.10 months
Answer: D.10 months
Explanation: Solution
P.W = Rs. (1760 - 160) = Rs. 1600.
∴ S.I on Rs.1600 ar 12% is Rs. 160.
∴ Time = ( 100 x160/1600 x 12) = 5/6 = ( 5/6x12 ) months = 10 months.
Answer D
Question: Two trains 140 m and 200 m long run at the speed of 60 km/hr and 40 km/hr respectively in opposite directions on parallel tracks. The time which they take to cross each other is?
A.10.9 sec
B.8.64 sec
C.53.8 sec
D.10.8 sec
Answer: B.8.64 sec
Explanation: Relative speed = 60 + 40 = 100 km/hr.
= 100 * 5/18 = 250/9 m/sec.
Distance covered in crossing each other = 140 + 200 = 240 m.
Required time = 240 * 9/250 = 8.64 sec.
Answer: B:
Question: The sum of the digits of a two-digit number is 15 and the difference between the digits is 3. What is the two-digit number?
A.79
B.56
C.81
D.Cannot be determined
Answer: D.Cannot be determined
Explanation: Let the ten's digit be x and unit's digit be y.
Then, x + y = 15 and x - y = 3 or y - x = 3.
Solving x + y = 15 and x - y = 3, we get: x = 9, y = 6.
Solving x + y = 15 and y - x = 3, we get: x = 6, y = 9.
So, the number is either 96 or 69.
Hence, the number cannot be determined.
Answer:D
Question: A candidate got 32% of the votes polled and he lost to his rival by 1908 votes. How many votes were cast?
A.5100
B.5200
C.5300
D.5400
Answer: C.5300
Explanation: Let x be the total number of votes.
0.32x + 1908 = 0.68x
0.36x = 1908
x = 1908/0.36 = 5300
The answer is C.
Question: A can do a job in 15days and B in 20days. If they work on it together for 5 days, then the fraction of the work that is left is?
A.2/15
B.8/15
C.3/11
D.5/12
Answer: D.5/12
Explanation: A's 1 day work = 1/15
B's 1day work = 1/20
A+B 1day work = 1/15 + 1/20 = 7/60
A+B 5days work = 7/60*5 = 7/12
Remaining work = 1 - 7/12 = 5/12
Answer is D
Question: A and B walk around a circular track. They start at 9 a.m. from the same point in the opposite directions. A and B walk at a speed of 2 rounds per hour and 3 rounds per hour respectively. How many times shall they cross each other before 10.30 a.m.?
A.8
B.7
C.12
D.5
Answer: C.12
Explanation: Sol.
Relative speed = (2 + 3) = 5 rounds per hour.
So, they cross each other 5 times in an hour and 2 times in half an hour.
Hence, they cross each other 12 times before 10.30 a.m.
Answer C
Question: A can do a job in 20 days and B can do it in 30 days. A and B working together will finish twice the amount of work in ------- days?
A.24 days
B.22 ½ days
C.23 ½ days
D.12 ½ days
Answer: A.24 days
Explanation: Explanation:
1/20 + 1/30 = 5/60 = 1/12
12 = 12 *2 = 24 days
Answer: A
Question: Which of the following inequalities has a solution set, when graphed on the number line, is a single line segment of finite length?
A.2 <= 5x+6 <= 6
B.2 <= 3x+4 <= 6
C.2 <= 5x+4 <= 6
D.2 <= 3x+7 <= 6
Answer: B.2 <= 3x+4 <= 6
Explanation: The key words in the stem are:a singleline segment offinite length
Now, answer choices A, B, and C can not be correct answers as solutions sets for these exponential functions are not limited at all (>= for even powers and <= for odd power) and thus can not be finite (x can go to + or -infinity for A and C and x can got to -infinity for B). As for D: we have thatabsolute valueof x is between two positive values, thus the solution set for x (because of absolute value) will be two line segments which will be mirror images of each other.
Answer: B.
Question: U(x, y) is the intersection point between the circle (x^2 + y^2 = 4) and the line (y = x +2). Which of the following can be the point U?
A.(1, 2).
B.(2, 0).
C.(0, -2).
D.(-2, 0).
Answer: D.(-2, 0).
Explanation: A quick glance at the options,U(x, y) and we can see that A and E do not satisfy the circle equation. Now we are left with B, C and D. Now B and C do not satisfy the line equation. So we are just left with D. And thats the answer=D
Question: If a man lost 8% by selling oranges at the rate of 25 a rupee at how many a rupee must he sell them to gain 25%?
A.20
B.15
C.18.4
D.20
Answer: C.18.4
Explanation: 92% ---- 25
125% ---- ?
92/125* 25 = 18.4
Answer: C
Question: There are 2 bars of gold-silver alloy; one piece has 2 parts of gold to 3 parts of silver and another has 3 parts of gold to 7 parts of silver. If both bars are melted into 8 kg bar with the final gold to silver ratio of 5:11. What was the weight of the first bar?
A.1 kg
B.3 kg
C.5 kg
D.6 kg
Answer: A.1 kg
Explanation: irst bar is x kg, then second bar is (8-x)kg
First bar:
Amt of gold = 2x/5kg
Amt of silver = 3x/5 kg
Second bar:
Amt of gold = 3(8-x)/10 kg
Amt of silver = 7(8-x)/10 kg
Total amt of gold = 2x/5 + 3(8-x)/10 = (4x+24-3x)/10 = (x+24)/10 kg
Total amt of silver = 3x/5 + 7(8-x)/10 = (6x+56-7x)/10 = (56-x)/10 kg
Ratio of gold/silver = 5/11 = (x+24)/10 * 10/(56-x)
5/11 = (x+24)/(56-x)
5(56-x) = (x+24)(11)
x = 1kg
ANSWER:A
Question: Watermelon Computer Company began production in 2001 with a total of only 10 employees. From 2001 to 2006, the total number of employees increased to 500. From 2001 to 2016, the total number of employees increased to 5,000. What was the percentage increase of employees from 2006 to 2016?
A. 10,000%
B. 6,700%
C. 2,000%
D. 3,000%
Answer: D. 3,000%
Explanation: The percentage increase of employees 2006-16 is calculated by;
(100)[(total employees 2001-16) - (total employees 2001-06)]/(total employees 2006) percent.
Solution:(100) [(5,000-500)/150]% = 3,000%
Answer is D
Question: If 75 % of a boys answered the first question on a certain test correctly, 55 % answered the second question on the test correctly, and 20 % answered neither of the questions correctly, what % answered both correctly?
A. 10%
B.(8) 20%
C. 50%
D. 60%
Answer: C. 50%
Explanation: {Total} = {First} + {Second} - {Both} + {Neither}
100% = 75% + 55% - {Both} + 20% --> {Both} = 50%.
Answer: C
Question: What least number should be subtracted from 13601 such that the remainder is divisible by 87 ?
A.27
B.29
C.28
D.30
Answer: B.29
Explanation: 13601 ÷ 87 = 156, remainder = 29
Hence 29 is the least number which can be subtracted from 13601 such that the remainder
is divisible by 87
Answer is B
Question: If 3 persons can do 3 times of a particular work in 3 days, then, 7 persons can do 7 times of that work in?
A.3 days
B.5 days
C.7 days
D.11 days
Answer: A.3 days
Explanation: That is, 1 person can do one time of the work in 3 days.
Therefore, 7 persons can do 7 times work in the same 3 days itself.
A)
Question: A can do a half of certain work in 60 days and B one third of the same in 35 days. They together will do the whole work in.
A.56 days
B.420 days
C.46 days
D.560 days
Answer: A.56 days
Explanation: A = 120 days
B = 105 days
1/120 + 1/105 = 45/2520 = 1/56
=>56 days
ANSWER:A
Question: If x = -5/4 and y = -3/2, what is the value of the expression -2x – y^2?
A.1/4
B.-1
C.5/4
D.3/2
Answer: A.1/4
Explanation: x = -5/4 and y = -3/2
==> -2(-5/4) - (3/2)^2 = 10/4 - 9/4 = 1/4
Ans: A
Question: The ratio of number of ladies to gents at a party was 1 : 2, but when 2 ladies and 2 gents left, the ratio became 1 : 3. How many people were originally present at the party?
A.6
B.9
C.12
D.10
Answer: C.12
Explanation: Let number of ladies = x
then, number of gents = 2x
Now, x−2/2x−2=13⇒ 3x - 6 = 2x - 2
⇒ x = 4
∴ Total number of people originally present = 4 + 8 = 12
Answer C
Question: The number which exceeds 12% of it by 52.8 is:
A.50
B.52
C.58
D.60
Answer: D.60
Explanation: Explanation:
Let the number be x. Then, x – 12% of x = 52.8
x – (12/100)x = 52.8
x (1– 12/100) = 52.8
(88/100)x = 52.8
x = (100 X 52.8) / 88 = 60
ANSWER D
Question: Baney covered a distance of 340 miles between city A and city B taking a total of 5 hours. If part of the distance was covered at 60 miles per hour speed and the balance at 80 miles per hour speed, how many hours did she travel at 60 miles per hour?
A.1 hour 45 minutes
B.2 hours
C.2 hours 30 minutes
D.3 hours
Answer: D.3 hours
Explanation: Baney covered a distance of 340 miles between city A and city B taking a total of 5 hours.time taken at 60:time taken at 80::(greater speed-average speed):(average speed-lower speed)
average speed is 340/5=68
That gives the answer 3:2=D
Question: An exam consists of 200 questions to be solved in 3 hours, out of which 50 are maths questions. It is suggested that twice as much time be spent on each math question as for each other question. How many minutes should be spent on maths problems?
A.36/25 minutes
B.36/24 minutes
C.36/26 minutes
D.35/25 minutes
Answer: A.36/25 minutes
Explanation: x=time for each math problem
y= time for every other problem
50x+150y=180 minutes
x=2y because spent twic as much time on the math problems as the other
50(2y)+150y=180
100y+150y=180
250y=180
y= 180/250=18/25 of a minute per problem on the other questions
x=2(18/25)
x=36/25 minutes
ANSWER:A
Question: I am five letter word. if you remove one, only two letters remain.
What word am I
A.I am phone
B.I am table
C.I am Water
D.I am Stone
Answer: D.I am Stone
Explanation: Correct Answer : D
Stone is five letter word. If your remove one from stone(not 1letter) we will get St
Question: Albert completes a piece of work in 20 days, Rose completes the same work in 30 days. If both of them work together, then the number of days required to complete the work is?
A.10
B.12
C.15
D.20
Answer: B.12
Explanation: If A can complete a work in x days and B can complete the same work in y days, then, both
of them together can complete the work in x y/ x+ y days.
That is, the required No. of days = 20 × 30/50 = 12 days
Answer is B
Question: Ernie invested Rs. 2000, with compounded interest annually. After 3 and half years the investment doubled. How many more years will it take before he earns another Rs. 4000 compound interest?
A.3.5 years
B.1.5 years
C.2.5 years
D.3 years
Answer: A.3.5 years
Explanation: Explanatory Answer
Rs.2000 invested in compound interest becomes Rs.4000 in 3.5 years.
The amount will double again in another 3.5 years.
i.e., the amount will become Rs.4000 in another 3.5 years.
So, to earn another Rs.4000 interest, it will take another 3.5 years.
Answer A
Question: Ratio between Rahul and Deepak is 4:3, After 6 Years Rahul age will be 30 years. What is Deepak present age?
A.18
B.15
C.77
D.266
Answer: A.18
Explanation: Present age is 4x and 3x,
=> 4x + 6 = 30 => x = 6
So Deepak age is = 3(6) = 18
Answer: A
Question: A wheel that has 14cogs is meshed with a larger wheel of 28cogs. When the smaller wheel has made 20evolutions, then the number of revolutions mad by the larger wheel is:
A.20
B.11
C.12
D.10
Answer: D.10
Explanation: D
10
Let the required number of revolutions made by larger wheel be x.
Then, More cogs, Less revolutions (Indirect Proportion)
28 : 14 :: 20 : x <-> 28 x x = 14 x 20
x = (14 x 20)/28
x =10
Question: A man can row 6 kmph in still water. When the river is running at 1.2 kmph, it takes him 1 hour to row to a place and black. What is the total distance traveled by the man?
A.5.79
B.5.71
C.5.76
D.5.79
Answer: C.5.76
Explanation: M = 6
S = 1.2
DS = 7.2
US = 4.8
x/7.2 + x/4.8 = 1
x = 2.88
D = 2.88 * 2 = 5.76
Answer: C
Question: √5 percent of 5√5 =
A.0.05
B.0.25
C.0.5
D.2.5
Answer: B.0.25
Explanation: √/1005/100* 55√5
= (5*5∗5− − √5∗5 )/100
= (5*5) /100
= 25/100
=.25
ANSWER:B
Question: A and B started a partnership business investing some amount in the ratio of 3 : 5. C joined then after six 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 : 5
D.7 : 9: 4
Answer: C.6 : 10 : 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 6) = 36 : 60 : 30
= 6 : 10 : 5.
ANSWER :C
Question: Out of 450 students of a school, 325 play football, 175 play cricket and 50 neither play football nor cricket. How many students play both football and cricket ?
A.75
B.100
C.125
D.150
Answer: B.100
Explanation: Explanation:
Students who play cricket, n(A) = 325
Students who play football, n(B) = 175
Total students who play either or both games,
=n(AâˆªB)=450âˆ’50=400Required Number,n(Aâˆ©B)=n(A)+n(B)âˆ’n(AâˆªB)=325+175âˆ’400=100
ANSWER IS B
Question: If a boat goes 6 km upstream in 90 minutes and the speed of the stream is 3 kmph, then the speed of
the boat in still water is
A.12 kmph
B.7 kmph
C.14 kmph
D.15 kmph
Answer: B.7 kmph
Explanation: Explanation:
Rate upstream = (6/90)*60 kmh = 4 kmph.
Speed of stream = 3 kmph.
Let speed in still water is x km/hr
Then, speed upstream = (x ï¿½3) km/hr.
x-3 = 4 or x = 7 kmph
Answer: B
Question: What is the greatest prime factor of 9!8! + 8!7! ?
A.23
B.43
C.53
D.73
Answer: D.73
Explanation: 9!8! + 8!7! = 8!7!(9*8+1) = 8!*7!*73
The answer is D.
Question: The owner of a cell phone shop charges his customer 23% more than the cost price. If a customer paid Rs.7,190 for a cell phone, then what was the cost price of the cell phone?
A.Rs.5,845
B.Rs.6,750
C.Rs.5,700
D.Rs.6,925
Answer: A.Rs.5,845
Explanation: Explanation:
123% of CP =SP
Therefore, CP = Rs.7,190x100/123 = Rs.5845
Answer: Option A
Question: The maximum numbers of students among them 891 pens and 810 pencils can be distributed in such a way that each student gets the same number of pens and same number of pencils is
A.91
B.81
C.1001
D.1911
Answer: B.81
Explanation: olution
Required number of students.
= H.C.F of 891 and 810.
â€¹=â€º 81.
Answer B
Question: If the two hands in a clock are 3 minutes divisions apart,then the angle between them is
A.3°
B.18°
C.24°
D.60°
Answer: B.18°
Explanation: In a clock, each minute makes 6°
∴ 3 minutes will make 6 × 3 = 18°
Answer B
Question: A drove of sheep and chickens have a total of 99 heads and feet. There are twice as many chickens as sheep. How many of each are there?
A.18,9
B.17,9
C.1,9
D.16,9
Answer: A.18,9
Explanation: let chicken be x and sheep be y
x=2y (given)
3x+5y=99 (chicken has two legs and one head i.e 3 likewise sheep=5
y=9
x=18
ANSWER:A
Question: The probability that a man will be alive for 10more yrs is 1/2 & the probability that his wife will alive for 10 more yrs is 1/3. The probability that none of them will be alive for 10 more yrs, is
A.1/2
B.1
C.1/3
D.3/4
Answer: C.1/3
Explanation: Sol. Required probability = Pg.) x P(B) = (1— D x(1 —I) =: x 1=1/3
Ans.(C)
Question: A set of numbers has an average of 20. If the largest element is 4 greater than 3 times the smallest element, which of the following values cannot be in the set?
A. 55
B. 90
C. 23
D. 50
Answer: B. 90
Explanation: Ans: B
Solution: we are given the relation between smallest and the largest term. so let the smallest a and largest be 3a+4
so the avg = 50
which tells us that any value of a must be less than 20
so a<50 means, largest value 3a+4 <(3*20)+4
=largest value must be <64
so 64 can not be the value in the set.
Question: A shopkeeper buys mangoes at the rate of 4 a rupee and sells them at 3 a rupee. Find his net profit or loss percent?
A.33 1/8 %
B.33 8/3 %
C.33 1/3 %
D.93 1/3 %
Answer: C.33 1/3 %
Explanation: The total number of mangoes bought by the shopkeeper be 12.
If he buys 4 a rupee, his CP = 3
He selling at 3 a rupee, his SP = 4
Profit = SP - CP = 4 - 3 = 1
Profit Percent = 1/3 * 100 = 33 1/3 %
Answer:C
Question: The weights of one liter vegetable ghee packet of two brands ‘A’ and ‘B’ are 900 gm and 800 gm respectively. If they are mixed in the ratio of 3 : 2 by volumes to form a mixture of 4 liters, what is the weight (in kg) of the mixture?
A.3.84
B.1.75
C.3.44
D.2.72
Answer: C.3.44
Explanation: Here's how I did it. My notes from reading the problem were:
1L A = 900 gm
1L B = 800 gm
We are mixing five parts (3 parts A plus 2 parts B, 5 parts total) to get 4L, so 5x = 4 ---> x = 4/5. Each part is 4/5 of a liter.
So if we have 3 parts A, we have 900*3*(4/5) = 2160
If we have 2 parts B, we have 800*2*(4/5) = 1280
2160 + 1280 = 3440
Solving for units gives us 3.44
So the answer is C
Question: A 300 meter long train crosses a platform in 39 seconds while it crosses a signal pole in 18 seconds. What is the length of the platform?
A.388
B.656
C.350
D.771
Answer: C.350
Explanation: Speed = [300 / 18] m/sec = 50/3 m/sec.
Let the length of the platform be x meters.
Then, x + 300 / 39 = 50/3
3(x + 300) = 1950 è x = 350m.Answer: C
Question: A invested some money in 10% stock at 96. If B wants to invest in an equally good 12% stock, he must purchase a stock worth of :
A.Rs.80
B.Rs.115.20
C.Rs.120
D.Rs.125.40
Answer: B.Rs.115.20
Explanation: Explanation:
For an income of Rs. 10, investment = Rs. 96.
For an income of Rs. 12, investment = (96/10x12) =115.20
Answer: B
Question: an isosceles triangle with sides 13 13 10 and there is a circle inscribed it .find the radius of circle?
A.1.32
B.3.33
C.3.58
D.4.34
Answer: B.3.33
Explanation: height of triangle = √(13^2 - (10/2)^2) = 12
area of triangle = r * s
where, r = radius of inscribed circle & s=(a+b+c)/2
area of triangle = 1/2 *b*h = 1/2 *10 *12 = 60
s = (13+13+10)/2 = 18
r = area of triangle / s = 60/18 = 10/3 = 3.33
ANSWER:B
Question: The price of 2 sarees and 4 shirts is Rs. 1600. With the same money one can buy 1 saree and 6 shirts. If one wants to buy 12 shirts, how much shall he have to pay ?
A.1800
B.2000
C.2200
D.2400
Answer: D.2400
Explanation: Let the price of a saree and a shirt be Rs. x and Rs. y respectively.
Then, 2x + 4y = 1600 .... (i)
and x + 6y = 1600 .... (ii)
Divide equation (i) by 2, we get the below equation.
= x + 2y = 800. --- (iii)
Now subtract (iii) from (ii)
x + 6y = 1600 (-)
x + 2y = 800
----------------
4y = 800
----------------
Therefore, y = 200.
Now apply value of y in (iii)
= x + 2 x 200 = 800
= x + 400 = 800
Therefore x = 400
Solving (i) and (ii) we get x = 400, y = 200.
Cost of 12 shirts = Rs. (12 x 200) = Rs. 2400.
answer : D
Question: Dany bought a total of 18 game cards some of which cost $0.25 each and some of which cost $0.15 each. If Dany spent $4.2 to buy these cards, how many cards of each type did he buy?
A.4
B.10
C.7
D.3
Answer: D.3
Explanation: Let X be the number of cards that cost $0.25 each and Y the number of cards that cost $0.15 each. The total number of cards is 18. Hence
X + Y = 18
If X is the number of cards at $0.25, then the X cards cost
0.25 X
If Y is the number of cards at $0.15, then the Y cards cost
0.15 Y
The total cost of the X cards and the the Y cards is known to be $4.2 and also given by
0.25 X + 0.15 Y = 4.2
We now need to solve the system of equations
X + Y = 18
0.25 X + 0.15 Y = 4.2
The first equation gives Y = 18 - X. Substitute y by 18 - x in the second equation and solve
0.25 X + 0.15 (18 - X) = 4.2
X(0.25 - 0.15) + 2.7 = 4.2
0.1 X = 1.5
X = 15 and Y = 18 - 15 = 3
correct answer D
Question: If you divide a number into 3 equal groups and then divide each group in half, you end up with 13. What number did you start with?
A.76
B.77
C.78
D.79
Answer: C.78
Explanation: Solution:
Suppose the start number is x Division into 3 equal groups is: x/3, and then in half is (x/3)/2 = 13
x/6 = 13
x = 13 * 6 = 78
Answer C
Question: A man can row a boat at 12 kmph in still water. If the speed of the stream is 4 kmph, what is the time taken to row a distance of 50 km downstream?
A.25/8
B.29/8
C.23/8
D.27/8
Answer: A.25/8
Explanation: Speed downstream = 12 + 4 = 16 kmph.
Time required to cover 50 km downstream = d/s = 50/16
= 25/8 hours.
Answer: A
Question: Find the greatest number which on dividing 1428 and 2206, leaves a reminder of 9 and 13 respectively
A.125
B.127
C.129
D.131
Answer: C.129
Explanation: Explanation:
In this type of question, its obvious we need to calculate the HCF, trick is
HCF of (1428 - 9) and (2206 -13)
= HCF (1419, 2193) = 129
Option C