RikoteMaster/aqua-rat-mcqa huggingface dataset:
Question: There are 8 students. 4 of them are men and 4 of them are women. If 4 students are selected from the 8 students. What is the probability that the number of men is equal to that of women?
A.18/35
B.16/35
C.14/35
D.13/35
Answer: A.18/35
Explanation: men= women means 2 men 2 women
total such combinations = 4c2 * 4c2 = 4!/2!.2! * 4!/2!.2! = 6*6
total combinations = 8c4 = 8*7*6*5/4*3*2*1 = 70
so probability = 36/70 = 18/35
hence A
Question: The diagonals of a rhombus are 15 cm and 12 cm. Find its area?
A.70
B.90
C.60
D.80
Answer: B.90
Explanation: 1/2 * 15 * 12
= 90
Answer:B
Question: The current of a stream at 1 kmph. A motor boat goes 35 km upstream and back to the starting point in 12 hours. The speed of the motor boat in still water is?
A.6
B.8
C.4
D.9
Answer: A.6
Explanation: S = 1
M = x
DS = x + 1
US = x - 1
35/(x + 1) + 35/(x - 1) = 12
x = 6
Answer: A
Question: If 45-[28-{37-(15-*)}]= 59, then * is equal to:
A.-29
B.-19
C.20
D.29
Answer: C.20
Explanation: 45-[28-{37-(15-*)}]= 59 => 45-[28-{37-15+*}]=59
45-[28-37+15-*]=59 => 45[43-37-*]=59
45-[6-*]=59 => 45-6+*=59
39+*=59 => *=59-39
= 20
ANSWER:C
Question: A sum of money lent out at S.I. amounts to Rs. 820 after 2 years and to Rs. 1020 after a further period of 5 years. The sum is?
A.Rs.440
B.Rs. 500
C.Rs. 540
D.Rs. 740
Answer: D.Rs. 740
Explanation: S.I for 5 years = (1020 - 820) = Rs. 200.
S.I. for 2 years = 200/5 * 2 = Rs. 80.
Principal = (820 - 80) = Rs. 740.
ANSWER:D
Question: At a contest with 2000 participants, 1/2 of the people are aged 16 to 18. Next year, the number of people aged 16 to 18 will increase by 1/4. After this change, what percentage of the total 2000 people will the 16- to 18- year-olds represent?
A.62.50%
B.60%
C.70%
D.65%
Answer: A.62.50%
Explanation: I just wanted to mention a couple of things here:
* this is a pure ratio question; the number 2000 is completely irrelevant, and you can ignore it if you like. When we increase something by 1/4, we are multiplying it by 1 + 1/4 = 5/4, so the answer here must be (1/2)*(5/4) = 5/8 = 62.50 %.
Answer : A
Question: Four milkmen rented a pasture. A grazed 24 cows for 3 months, B 10 cows for 5 months, C 35 cows for 4 months and D 21 cows for 3 months. If A’s share of rent is Rs.720, find the total rent of the field.
A.Rs.3250
B.Rs.3350
C.Rs.3450
D.Rs.3550
Answer: A.Rs.3250
Explanation: Ratio of shares of A, B, C, D = (24 * 3) : (10 * 5) : (35 * 4) : (21 * 3)
= 72 : 50 : 140 : 63
Let total rent be Rs.x. Then, A’s share = Rs. 72x/325.
Therefore, 72x/325 = 720 => x = 720 * 325/72 = 3250.
Hence, total rent of the field is Rs.3250.
ANSWER:A
Question: Sandy purchased 20 dozen toys at the rate of $144 per dozen. Sandy sold each toy at the rate of $15. What was the percentage profit?
A.15%
B.25%
C.35%
D.45%
Answer: B.25%
Explanation: A dozen toys cost $144, so each toy cost $12.
selling price / cost price = 15 / 12 = 1.25
The percentage profit is 25%.
The answer is B.
Question: The total number of digits used in numbering the pages of a book having 366 pages is
A.732
B.990
C.1098
D.1305
Answer: B.990
Explanation: Explanation:
Total number of digits
= (No. of digits in 1- digit page nos. + No. of digits in 2-digit page nos. + No. of digits in 3- digit page nos.)
= (1 x 9 + 2 x 90 + 3 x 267) = (9 + 180 + 801) = 990.
Answer: B
Question: If x is odd and y is odd, then x + y is
A.Odd
B.Odd whenever xy is even
C.Even whenever xy is odd
D.Even
Answer: D.Even
Explanation: x is odd and y is odd, then x + y is
Let's take x=9 and y=5.
x+y=9+5=14.
x+y=14=even.
Option: D
Question: A box contains 3 blue marbles, 4 red, 6 green marbles and 2 yellow marbles. If two marbles are picked at random, what is the probability that they are either blue or yellow?
A.2/27
B.2/29
C.2/21
D.2/22
Answer: C.2/21
Explanation: Given that there are three blue marbles, four red marbles, six green marbles and two yellow marbles. Probability that both marbles are blue = ³C₂/¹⁵C₂ = (3 * 2)/(15 * 14) = 1/35
Probability that both are yellow = ²C₂/¹⁵C₂ = (2 * 1)/(15 * 14) = 1/105
Probability that one blue and other is yellow = (³C₁ * ²C₁)/¹⁵C₂ = (2 * 3 * 2)/(15 * 14) = 2/35
Required probability = 1/35 + 1/105 + 2/35
= 3/35 + 1/105 = 1/35(3 + 1/3)
= 10/(3 * 35) = 2/21
Answer:C
Question: A highway is to be divided into four lanes. For this purpose, three yellow stripes are painted so that stripes divide the highway into four lanes. If 3 gallons of paint cover an area of 5P square feet of highway, how many gallons of paint are needed to paint two stripes x inches wide on a stretch of highway m miles long? (1 mile = 5280 feet and 1 feet = 12 inches)
A.792mx/P
B.264mx/P
C.792P/mx
D.264P/mx
Answer: A.792mx/P
Explanation: 1 square foot needs 3/5P gallons of paint.
The width of each stripe is x/12 feet.
The length of each stripe is 5280m feet.
The area of each stripe is (5280m)(x/12) = 440mx square feet.
For three stripes, the total area is 1320mx square feet.
The number of gallons needed is (1320mx)*(3/5P) = 792mx/P gallons.
The answer is A.
Question: In how many years, Rs. 75 will produce the same interest at 6% as Rs. 800 produce in 2 years at 4½% ?
A.4 years
B.16 years
C.8 years
D.9 years
Answer: B.16 years
Explanation: Explanation :
Let Simple Interest for Rs.75 at 6% for n years = Simple Interest for Rs.800 at 4½ % for 2 years
75×6×n/100=800×9/2×2/100
75×6×n=800×9/2×2
75×6×n=800×9
n=16 years
Answer : Option B
Question: Three 6 faced dice are thrown together. The probability that all the three show the same number on them is ?
A.1/38
B.1/36
C.1/39
D.1/31
Answer: B.1/36
Explanation: It all 3 numbers have to be same basically we want triplets. 111, 222, 333, 444, 555 and 666. Those are six in number. Further the three dice can fall in 6 * 6 * 6 = 216 ways.
Hence the probability is 6/216 = 1/36
Answer:B
Question: If two dice are thrown together, the probability of getting an even number on one die and an odd number on the other is ?
A.1/6
B.1/2
C.1/9
D.1/1
Answer: B.1/2
Explanation: The number of exhaustive outcomes is 36.
Let E be the event of getting an even number on one die and an odd number on the other. Let the event of getting either both even or both odd then = 18/36 = 1/2
P(E) = 1 - 1/2
= 1/2.
Answer: B
Question: If S is a positive integer, which of the following must be odd?
A.S+1
B.S^2+S
C.S^2+S+1
D.x^2−1
Answer: C.S^2+S+1
Explanation: A. S+1 = can be odd or even. Since O + O =E or E + O = O
B. S^2 + S = S(S+1). Since from the above derivation we already know the term S+1 can be Odd or Even, directly substitute here. S(ODD) = Even (When S is Even) or S(EVEN) = EVEN [When S is ODD]
C. Here's the answer. Since we know the term S^2 + S can always take a EVEN number, EVEN + 1 = ODD
Hence C.
Question: Present birth rate is 32 per thousand while death rate is 11 per thousand. What will be the percentage increase in the rate of population?
A.0.21%
B.21%
C.0.021%
D.2.1%
Answer: D.2.1%
Explanation: birth rate=32/1000=0.032
death rate=11/1000=0.011
increase in population=0.032-0.011=0.021=2.1%
ANSWER:D
Question: The instructions state that Cheryl needs 2/9 square yards of one type of material and 1/8 square yards of another type of material for a project. She buys exactly that amount. After finishing the project, however, she has 4/18 square yards left that she did not use. What is the total amount of square yards of material Cheryl used?
A.1/12
B.1/9
C.1/8
D.1 1/9
Answer: C.1/8
Explanation: Total bought = 2/9+1/8
left part 4/18--->2/9
so used part 2/9+1/8-2/9=1/8
ANSWER:C
Question: Arnold wanted to create a perfect shade of pink for his new canvas painting. He started out replacing 25% of a 100% red colored paint with white. He then further replaced 15% of this shade with white. Finally, he repeated the process by replacing 10% of the shade with white. What was the final percentage of red in Arnold's pink paint?
A.62.40%
B.51%
C.68.21%
D.57.37%
Answer: D.57.37%
Explanation: Quick answer: 100x0.75x0.85x0.9
We begin with 100% red paint. 25% of this is replaced with white paint which leaves us with a mixture of 75% red paint (as 25% is white)
Next, 15% of this mixture is further mixed with white paint. That implies that 85% of the previous red paint remains. Hence, the new percentage is 75x0.85% = 63.75%
Finally, 10% of the new paint mixture is again mixed with white. This leaves us with 90% of the previous red quantity. So the final percentage of red is 63.75x0.9% = 57.37%
Answer: D
Question: In a certain random experiment, exactly one of the outcomes A, B, and M will occur. In each random experiment, the probability that outcome A will occur is 1/3 , and the probability that outcome B will occur is 1/3. What is the probability that when the random experiment is conducted 6 independent times, each of outcomes A, B, and M will occur twice?
A.5/243
B.1/12
C.10/81
D.1/6
Answer: C.10/81
Explanation: Number of ways in which a group of 2A,2B,2M can be formed in any order = 6!/(2!*2!*2!) [ formula for total of 6 items with 2 each of similar kind)
Total number of ways in which the die can be thrown independently = _ _ _ _ _ _ ; there are 6 places .First can be filled in 3 different ways A/B/M; Second in 3 diff ways again and so on.
So total number of ways = 3X3X3X3X3X3 = 3^6
There fore probability = 6!/(2!x2!x2!) by 3^6 = 90/3^6 = 10/81 Answer C
Question: A man buys a cycle for Rs. 1600 and sells it at a loss of 15%. What is the selling price of the cycle?
A.s. 1090
B.s. 1360
C.s. 1190
D.s. 1202
Answer: B.s. 1360
Explanation: S.P. = 85% of Rs. 1600 = Rs.85/100x 1600	= Rs. 1360
ANSWER :B
Question: At present, the ratio between the ages of Arun and Deepak is 5:4. After 5 years, Arun's age will be 40 years. What is the age of Deepak at present?
A.28
B.26
C.24
D.22
Answer: A.28
Explanation: Let the present ages of Arun and Deepak be 5x and 4x years respectively.
Then, 5x + 5 = 40 => x = 7
Deepak's age = 4x = 28 years.
Answer: A
Question: Twenty four men can do a work in 35 days. How many men are required to complete the work in 21 days?
A.11
B.40
C.99
D.77
Answer: B.40
Explanation: We have M1 D1 = M2 D2
So, 24 * 35 = M2 * 21 => M2
= 40.
Answer: B
Question: An express traveled at an average speed of 100 km/hr, stopping for 3 min after every 75 kn. How long did it take to reach its destination 600 km from the starting point?
A.5 hrs 21 min
B.4 hrs 21 min
C.6 hrs 41 min
D.6 hrs 21 min
Answer: D.6 hrs 21 min
Explanation: D
6 hrs 21 min
Time taken to cover 600 km = 600/100 = 6 hrs.
Number of stoppages = 600/75 - 1 = 7
Total time of stoppages = 3 * 7 = 21 min
Hence, total time taken = 6 hrs 21 min.
Question: In a kilometer race, A beats B by 20 meters or 10 seconds. What time does A take to complete the race?
A.490 sec
B.190 sec
C.176 sec
D.716 sec
Answer: A.490 sec
Explanation: Time taken by B run 1000 meters
= (1000 * 10)/20 = 500 sec.
Time taken by A = 500 - 10
= 490 sec.
Answer:A
Question: A group of 4 students bought movie tickets in one row next to each other. If Bob and Lisa are in this group, what is the probability that Bob and Lisa will each sit next to only one of the three other students from the group?
A.5.55%
B.16.67%
C.15.75%
D.20.45%
Answer: B.16.67%
Explanation: The question basically asks about the probability that Bob and Lisa sit at the ends.
The total # of sitting arrangements is 4!.
Desired arrangement is either BYZL or LYZB. Now, YZ can be arranged in 2! ways, therefore total # of favorable arrangements is 2*2!.
P=(favorable)/(total)=(2*2!)/4!=1/6.
Answer: B.
Question: If 6 (A's capital) = 8 (B's capital) = 10 (C's capital). Then the ratio of their capitals is:
A.20:15:16
B.20:15:11
C.20:15:12
D.20:15:18
Answer: C.20:15:12
Explanation: 6A = 8B = 10 C
A:B:C = 1/6:1/8:1/10
= 20:15:12
Answer:C
Question: Find the invalid no.from the following series 3, 7, 15, 27, 63, 127, 255
A.3
B.7
C.27
D.63
Answer: C.27
Explanation: Go on multiplying the number by 2 and adding 1 to it to get the next number.So, 27 is wrong.
C
Question: (1.00001)(0.99999) - (1.00006)(0.99994) =
A.35(10^-10)
B.10^-10
C.3(10^-10)
D.10^-5
Answer: A.35(10^-10)
Explanation: (1.00001*0.99999)-(1.00006*0.99994)
= (1+0.00001)(1-0.00001) - (1+0.00006)(1-0.00006)
= 1 - (0.00001)^2 - 1 + (0.00006)^2
= -(0.0000000001) + (0.0000000036)
= 0.0000000035=35(10^-10)
Answer A
Question: Find ? x 11 = 555555
A.505
B.5050
C.50505
D.5005
Answer: C.50505
Explanation: Answer
Let N x 11 = 555555
Then N = 555555 / 11 = 50505.
Correct Option: C
Question: In 1982 and 1983, Company B’s operating expenses were $12.0 million and $13.0 million, respectively, and its revenues were $15.6 million and $18.8 million, respectively. What was the percent increase in Company B’s profit (revenues minus operating expenses) from 1982 to 1983 ?
A.3%
B.61 1/9%
C.25%
D.33 1/3%
Answer: B.61 1/9%
Explanation: Profit in 1982 = 15.6 - 12 = 3.6 million $
Profit in 1983 = 18.8 - 13 = 5.8 million $
Percentage increase in profit = (5.8-3.6)/3.6 * 100 %
= 61 1/9 %
Answer B
Question: Avg cost of 3 sharpners and 6 erasers is Rs.72. The avg cost of 6 sharpners and 8 erasers is Rs.112. Find the total cost of 20 sharpners and 20 erasers?
A.190
B.160
C.130
D.200
Answer: B.160
Explanation: Avg cost of 3 sharpners and 6 erasers is Rs.72
(3 sharpner + 6 erasers) 9=72
therefore 1 sharpner cost is 72/9=8, so 3 sharpner cost is 3x8=24 and 6 erasers cost is 6x8=48
Again, avg cost of 6 sharpners and 8 erasers is Rs.112
(6 sharpner + 8 erasers) 14=112
therefore 1 sharpner cost is 112/14=8, so 6 sharpner cost is 6x8=48 and 8 erasers cost is 8x8=64
So 20 sharpner cost is (20/a)=160 and 20 erasers cost is (20x8)=160
ANSWER:B
Question: A vessel contains 20 liters of a mixture of milk and water in the ratio 3:2. 10 liters of the mixture are removed and replaced with an equal quantity of pure milk. If the process is repeated once more, find the ratio of milk and water in the final mixture obtained?
A.9:1
B.8:1
C.9:8
D.2:1
Answer: A.9:1
Explanation: Milk = 3/5 * 20 = 12 liters, water = 8 liters
If 10 liters of mixture are removed, amount of milk removed = 6 liters and amount of water removed = 4 liters.
Remaining milk = 12 - 6 = 6 liters
Remaining water = 8 - 4 = 4 liters
10 liters of pure milk are added, therefore total milk = (6 + 10) = 16 liters.
The ratio of milk and water in the new mixture = 16:4 = 4:1
If the process is repeated one more time and 10 liters of the mixture are removed, then amount of milk removed = 4/5 * 10 = 8 liters.
Amount of water removed = 2 liters.
Remaining milk = (16 - 8) = 8 liters.
Remaining water = (4 -2) = 2 liters.
The required ratio of milk and water in the final mixture obtained = (8 + 10):2 = 18:2 = 9:1.
Answer:A
Question: Simplify
80âˆ’[5âˆ’(6+2(7âˆ’8âˆ’5Â¯Â¯Â¯Â¯Â¯Â¯Â¯Â¯Â¯Â¯Â¯))]
A.23
B.25
C.89
D.30
Answer: C.89
Explanation: Explanation:
=80âˆ’[5âˆ’(6+2(7âˆ’8+5))]
(Please check due to overline, sign has been changed)
=80âˆ’[5âˆ’(6+2Ã—4))]
=80âˆ’[âˆ’9]=80+9=89
Option C
Question: ABCD is a square where AB =âˆš6016. Let X be a point on AB and Y be a point on CD such
that AX = CY . Compute the area of trapezoid AXYD.
A.3008
B.2002
C.1008
D.2016
Answer: A.3008
Explanation: Note that trapezoids AXY D and BXY C are congruent, so the area of AXY D is
always
6016/2= 3008 .
correct answer A
Question: 33
a3
+4b
___
88
If a and b represent positive single digits in the correctly worked computation above, what is the value of the two digit integer ab?
A.12
B.10
C.13
D.24
Answer: A.12
Explanation: 3+3+b=8
b=2
3+a+4=8
a=1
ab=12
ans=A
Question: A train running at 1/4 of its own speed reached a place in 12 hours. How much time could be saved if the train would have run at its own speed?
A.9 hrs
B.10hrs
C.12hrs
D.15hrs
Answer: A.9 hrs
Explanation: time taken if run its own speed = 1/4*12 = 3 hrs
Time saved = 12 - 3 = 9 hrs
Answer : A
Question: How much pure alcohol should be added to 400ml of a 15% solution to make the strength of solution 32%?
A.100 ml
B.60 ml
C.120 ml
D.130 ml
Answer: A.100 ml
Explanation: 400ml has 15% alcohol i.e 60ml . This means we have 340ml of water or the liquid with which alcohol is mixed
Let V be the volume of alcohol added to make the strength 32%
then V/340+V = 32/100. solving this we get V as 160ml
so we need to add 160 -60 = 100 ml of alcohol
ANSWER:A
Question: The tailor has a 10 meter long piece of fabric for which to sew a ball room dress.
She has to cuts this fabric into strips of 200 centimeters each.
How long will it take the tailor to complete this tasks if each 200 centimeter took 5 minutes to cut ?
A.150
B.200
C.188
D.245
Answer: D.245
Explanation: The tailors would need to cut the fabric 49 times thus the total amount spent would be 245 minutes. The answer is D
Question: Find the largest number of four digits which is exactly divisible by 26,18,12,15
A.9700
B.9710
C.9360
D.9130
Answer: C.9360
Explanation: Explanation:
LCM of 26-18-12-15 is 2340.
After dividing 9999 by 2340 we get 639 remainder.
So answer will be 9999-639 = 9360
Option C
Question: Eggs are sold in packages of six or eleven only. If Doris bought 78 eggs exactly, what could be the number of large packs Doris bought?
A.6.
B.2.
C.3.
D.5.
Answer: A.6.
Explanation: No strategy involved. Simple question demanding fast calculation.
11x6 = 66=> 78-66=12 => 12/6 is an integer
Ans A. 6.
Good luck
Question: There 3 kinds of books in the library physics, chemistry and biology. Ratio of physics to chemistry is 3 to 2; ratio of chemistry to biology is 4 to 3, and the total of the books is more than 3000. Which one of following can be the total W of the book?
A.3003
B.3027
C.3024
D.3021
Answer: A.3003
Explanation: First, you have to find the common ratio for all 3 books. You have:
P:C:B
3:2 --> multiply by 2 (gives you row 3)
4:6
6:4:3
Hence:
P:C:B:T(Total)W
6:4:3:13 ----> This means, the Total Number must be a multiple of 13.
Answer A is correct since 299 is divisible by 13, hence is 2990 and so is 3003 (2990+13).
Question: The sum of squares of two numbers is 80 and the square of their difference is 36. The product of the two numbers is.
A.22
B.44
C.58
D.116
Answer: A.22
Explanation: Explanation :
Let the numbers be x and y . Then
x2+y2=80 and (x−y)2=36
(x−y)2=36⇒x2+y2−2xy=36
⇒2xy=(x2+y2)−36=80−36=44
⇒xy=22
Correct Option: A
Question: A salesperson receives a base salary of $900 per month and a commission of 7.5% of the selling price of each item sold above the first 50 item. If this month she sold 210 items for $150 each, what will her monthly salary be?
A.$1,500
B.$1,800
C.$2,100
D.$2,700
Answer: D.$2,700
Explanation: Ans : 900+ 7.5 % * 150 * (210-50) = $ 2700
Answer D
Question: If both 112 and 33 are factors of the number a * 43 * 62 * 1311, then what is the smallest possible value of a?
A.121
B.3267
C.363
D.33
Answer: C.363
Explanation: Explanatory Answer
Step 1: Prime factorize the given expression
a * 43 * 62 * 1311 can be expressed in terms of its prime factors as a * 28 * 32 * 1311
Step 2: Find factors missing after excluding 'a' to make the number divisible by both 112 and 33
112 is a factor of the given number.
If we do not include 'a', 11 is not a prime factor of the given number.
If 112 is a factor of the number, 112 should have been in 'a'
33 is a factor of the given number.
If we do not include 'a', the number has only 32 in it.
Therefore, if 33 has to be a factor of the given number 'a' has to contain 31 in it.
Therefore, 'a' should be at least 112 * 3 = 363 if the given number has 112 and 33 as its factors.
The smallest value that "a" can take is 363.
Choice C is the correct answer.
Question: Of the students at a certain high school, 90 percent took a course in algebra or geometry and 10 percent took courses in both. If the percent of students who took a course in algebra was 3 times the percent of students who took a course in geometry, what percent of the students took a course in algebra but not geometry?
A.35%
B.45%
C.55%
D.65%
Answer: D.65%
Explanation: You can also just use the formula
n(A or B) = n(A) + n(B) - n(A and B)
90 = 3X + X - 10
X = 25
3X = 75
This is the number of people who took algebra including those who took both. To get the number of people who took only algebra, 75 - 10 = 65%
Answer (D)
Question: If a certain sample of data has a mean of 25.0 and a standard deviation of 3.0, which of the following values is more than 2.5 standard deviations from the mean?
A.12.0
B.13.5
C.17.5
D.23.5
Answer: C.17.5
Explanation: The standard deviation is 3. 2.5 standard deviations, which is just 2.5 x 3.0 is 7.5. The only answer more than 7.5 away from the mean is C.
Question: 45 x ? = 60% of 900
A.16.2
B.12
C.5
D.500
Answer: B.12
Explanation: Answer
Let 45 x A = (60 x 900)/100
∴ A = (60 x 9)/45 = 12
Correct Option: B
Question: A 500 meter long train crosses a signal post in 40 seconds. How long will it take to cross a 3 kilometer long bridge, at the same speed?
A.2 min 48 sec
B.4 min 48 sec
C.4 min 38 sec
D.4 min 18 sec
Answer: B.4 min 48 sec
Explanation: S = 500/40 = 12.5 mps
S = 3600/12.5 = 288 sec = 4 min 48 sec
ANSWER:B
Question: If an amount of Rs 42,460 is distributed equally
amongst 22 persons, how much amount would each
person get?
A.Rs 1905
B.Rs 2000
C.Rs 1930
D.Rs 765
Answer: C.Rs 1930
Explanation: Required amount =42460/22 = Rs 1930
Answer C
Question: What is the average of four tenths and two thousandths
A.0.2022
B.0.3325
C.0.201
D.0.2012
Answer: C.0.201
Explanation: Explanation:
Four tenths = 0.4
two thousandths = 0.002
The average is (0.4 + 0.002)/2 = 0.201
Answer: C
Question: If x^2 - 1 = 0 and x < 0, which of the following must be equal to 0 ?
A. x^2 - 9x
B. x^2 - 9x + 20
C. x^2 - 2x + 3
D. x^2 + 2x + 1
Answer: D. x^2 + 2x + 1
Explanation: x^2-1 = 0
x= +1 or x = -1
if we substitute x= -1 in the equation x^2 +2x+1 = 1-2+1 = 0
D is also the answer
Question: A factory has 500 workers, 18 percent of whom are women. If 50 additional workers are to be hired and all of the present workers remain, how many of the additional workers must be women in order to raise the percent of women employees to 20 percent?
A. 3
B. 10
C. 20
D. 30
Answer: C. 20
Explanation: Currently the factory has 0.18*500=90 women.
After 50 additional workers are hired, there will be total of 550 workers and we need 0.2*550=110 of them to be women, so we need 110-90=20 more women.
Answer: C.
Question: An airplane flies along the four sides of a square field at the speeds of 200, 400, 600 and 800 km/h. The average speed of the plane around the field in km/h is
A.384
B.400
C.500
D.284
Answer: A.384
Explanation: Explanation :
Let each side of the square field be x km.
So, average speed of the plane
= 4x/((x/800)+(x/600)+(x/400)+(x/200))
= (4*2400)/(3+4+6+12) = 9600/25
= 384
Answer : A
Question: If N = 2^0.1 and N^b = 16, b must equal
A.3/80
B.3/5
C.40
D.5/3
Answer: C.40
Explanation: 10/100 = 1/10
N = 2 ^ 1/10
N^b = 2^4
(2^1/10)^b = 2^4
b = 40
Answer: C
Question: Find the amount on Rs.5000 in 2 years, the rate of interest being 4% per first year and 5% for the second year?
A.3377
B.2678
C.5460
D.1976
Answer: C.5460
Explanation: 5000 * 104/100 * 105/100 => 5460
Answer: C
Question: A straight fence is to be constructed from posts 6 inches wide and separated by lengths of chain 9 feet long. If a certain fence begins and ends with a post, which of the following could not be the length of the fence in feet? (12 inches = 1 foot)
A.29
B.48
C.55
D.67
Answer: C.55
Explanation: There is one post for each length of chain, plus one final post at the end.
The length of the fence in feet is 9.5x + 0.5, where each is the number of chain lengths.
The length of the fence is an integer when x = 1,3,5,7,...
The length of the fence could be 10, 29, 48, 67, 86,...
The answer is C.
Question: In how many ways can the letters of the word ED456 be rearranged such that the numbers always appear together?
A.25
B.16
C.36
D.9
Answer: C.36
Explanation: ED456
456 will come together as a group which can be arranged in 3!=6ways.
456,E,D can be arranged in 3!=6 ways.
total possible arrangements = 6*6=36 ways
ANSWER:C