ARITHMETIC ABILITY 1

Thursday, April 29, 2010

Read the questions carefully and pick the correct answer.

1. If an article cost 50% of its selling price there was a profit of Rs60. What was the selling price?
A. 125
B. 120
C. 140
D. 200
Answer: Option B
Let the selling price be S.Cost price = C = 0.5SProfit = 0.5S0.5S = 60S = 120


2. A can do a piece of work in 10 days which can be done by B in 12 days. How long would it take to do the work together?
A. 4 (7/9)
B. 5(3/9)
C. 5(5/11)
D. 5(1/2)
Answer: Option C
Explanation:
In one day A can do 1/10 workIn one day B can do 1/12 workIn one day A+B =1/10+1/12=22/120 =11/60=60/11 = 5(5/11)

3. The denominator of a fraction is greater than its numerator by 5 but if 7 were added to the denominator the value of the fraction would then become (1/4)th . What is the fraction?
A. 4/9
B. 2/3
C. 5/11
D. 4/7

Answer: Option A
Explanation:
Let the fraction be a/bb = a+5 --I Also, a/b+7 =1/44a = b+7 --II Solving I+II,-a+b = 54a-b = 73a = 12a = 4, therefore b = 9 so 4/9

4. The sum of all 2 digit numbers which can be formed from 4 and 5 ?
A. 45
B. 99
C. 100
D. 101
Answer: Option B
Explanation:
45, 54sum = 45+54 = 99

5. Find the number whose double is greater than its half by 30.
A. 20
B. 30
C. 25
D. 23

Answer: Option A
Explanation:
Let the number be x2x-1/2x = 303/2x = 303x = 60x = 20

6. A divided Rs. 200 amongst 15 children giving some Rs. 20 and remaing Rs.10.How many children receive Rs. 20?
A. 7
B. 12
C. 10
D. 5
Answer: Option D

Explanation:
20x+10y = 200 --Ix+y = 15 --II20x+10y =200(-)10x+10y = 15010x = 50x = 5

7. If 3 apples are worth 2 bananas, how many bananas are 15 apples worth?
A. 15
B. 8
C. 10
D. 12

Answer: Option C
Explanation:
Apples
Bananas
3
2
15
?15*2/3 = 10 Bananas

8. A buys an item for Rs. 600 of which 12% is excise and 4% is sales tax . How much would A pay exclusive of taxes and excise?
A. 519.82
B. 521.33
C. 517.24
D. 518.00

Answer: Option C
Explanation:
cost exclusive of excise and tax = xexcise = 0.12Tax= 0.04X+0.16x = 600X = 600/1.16= 517.24
9. X has Rs. 6 with him. If 2/3 of what X has is 1/4of what Y has. How much does Y have?
A. 8
B. 16
C. 12
D. 14

Answer: Option B
Explanation:
x has Rs. 6.2/3 of x = 2/3*6 = Rs. 4Rs. 4 = 1/4 yY = 4*4 = 16

10. The sum of a number and its reciprocal is 1/2 . The sum of their squares is,
A. 9/4
B. 4/5
C. 5/3
D. 7/4

Answer: Option A
Explanation:
x+1/x = 1/2(x+1/x)2 = x2 + 2x1/x + 1/x2= x2 +2 +1/x2= x2 + 1/x2 + 2= 1/4+2=1+8/4= 9/4

11. X,Y,and Z take 20, 30 and 60 days respectively to complete a job independently. They set out to complete a job together . However Y leaves after 4 days and Z leaves after another 6 days . How many more days will it take for X alone to complete the job now?
A. 4
B. 3
C. 5
D. 6

Answer: Option A
Explanation:
x will complete 1/20 in one day.Y will complete 1/30 in one day.Z will complete 1/60 in one day.4 days = (1/20 + 1/30 + 1/60)*4= (3+2+1/60)*4= 6/60*4= 4/10= 2/5th complete6 days = (1/20 + 1/60)*6 = (3+1/60)*6= 4/60*6= 4/10 = 2/5total work complete = 2/5+2/5 = 4/5work remaining = 1/51/5/1/20=1/5*20/1= 4 days

12. A rectangular block of dimensions 5*6*7 cm. Is dropped into a cylindrical vesssed of radius 6 cm. And height 10 cm.. If the level of fluid in the cylinder rises by 4 cm. , what portion of the block is immersed in the fluid?
A. (22/7)*(15/18)
B. (22/7)*(24/35)
C. (22/7)*(22/34)
D. (22/7)*(12/15)

Answer: Option B
Explanation:
volume increase in cylinder=(volume of block *portion of it which is immersed)22/7*62*4 = 5*6*7( p)p = 22/7*36*4/5*6*7p = 22/7*24/35

13. The difference between a number and its square is 870. What is the number?
A. 42
B. 29
C. 30
D. 32

Answer: Option C
Explanation:
Let the number be x.X2-x = 870X2-30x+29x-870 = 0(x-30)(x+29) = 0x = 30

14. In an election , 60% of the voters exercised the franchise. Of these, 40% were women. The number of males exercising their franchise was 53040. How many eligible voters were there in all?
A. 125000
B. 150000
C. 230000
D. 153000

Answer: Option B
Explanation:
Let the no. of eligible voters = xThen, (0.6)(.6x) = 530400.36x = 53040x = 54000/0.36x = 150000

15. If the side of a square is increased by 3 cm., the area increases by 33 cm. The side of the square is
A. 5.5
B. 6
C. 2
D. 4

Answer: Option D
Explanation:
Let side of the square be x.(x+3)2 = x2 + 33x2+6x+9=x2+336x=24x=4

16. A sum of RS. 88000 is to be divided among A, B, and C such that for every rupee, A gets, B gets 75 paise and for every rupee, B gets , C gets 90 paise . How much is C's share?
A. 28345
B. 28563
C. 29887
D. 30500

Answer: Option C
Explanation:
A:B is 10:7.5B:C is 10:9A:B:C is 100:75:90C gets 90*88000/265=29887

17. A family uses a mixture of a blend of 2 coffees costing Rs. 30 and Rs. 60 respectively.If the family uses only the expensive variety, it will have to spend Rs.450 more. The annual consumption of coffee of the family is 20Kgs. In what ratio are the two blends being used?
A. 3:1
B. 2:3
C. 4:5
D. 2:1

Answer: Option A
Explanation:
--------Need Clear Exp.----Expensive brand cost = 20*60=1200Expense now = 1200-450=750Average cost of the mixture =750/20Rs.30 Rs. 60Rs. 750/20450/20 150/203:1

18. A buys a washing machine costing Rs.6000 on instalment basis. He pays Rs. 3000 cash at the time of delivery and subsequently 2 monthly instalments of Rs. 1575 each. The rate of interest charged p.a. is
A. 39%
B. 32%
C. 28%
D. 30%


Answer: Option D
Explanation:
Instalments paid = 1575+1575 = 3150Interest = 3150-3000 = 150For 2 months interest = Rs.150Rate of interest 2.5%p.m.Rate of interest p.a. = 12*2.5 = 30%

19.
If 4-[2.8-{3.5-(1-X)}]=5, Then value of X is
A. 2.3
B. 1.5
C. 1.3
D. 2.5
Answer: Option C
Explanation:
4-2.8+3.5-1+x=5x=5-4+2.8-3.5+1=1.3

20. A salesman earns a commission of 3% on the value of sale that he makes. If by selling a radio at 60 % of the marked prices, he earns a commission of Rs. 12, then the marked price of the radio is?
A. 667
B. 700
C. 655
D. 680

Answer: Option A
Explanation:
Let the marked price be 100.Selling price =60Commission = 3/100*60 = 1.8
Commission(%)
Commission(Rs).
1.8
12
100
?100*12/1.8=666.67