1. If a : b = 4 : 3 and b : c = 7 : 9, then a : b : c : ?
A. 24 : 21 : 30
B. 12 : 15 : 21
C. 8 : 6 : 12
D. 28 : 2l : 27
Answer - Option D
Explanation -
a : b = 4 : (3)* 7 = 4 *3 = 4 * 7 : 3 * 7
b : c 7 : (9)* 3 and 7 : 9 = 7 * 3 : 9 *3
a : b = 28 : 21
b : c = 21 : 27
i.e, a : b : c = 28 : 21 : 27
2. Ravi spends [latex]\frac{2}{5}[/latex] of his salary on House Rent; [latex]\frac{3}{10}[/latex] of his salary on Food and [latex]\frac{1}{8}[/latex] of his Salary on Conveyance. After this, he is left with Rs. 1400. Find his expenditure on Food
A. Rs. 8000
B. Rs. 3200
C. Rs. 2400
D. Rs. 1000
Answer - Option C
Explanation -
Let the salary of Ravi be Rs. x
Total expenditure = [latex]x \frac{2}{5}[/latex] + [latex]x \frac{3}{10}[/latex] + [latex]x \frac{1}{8}[/latex] = [latex]x \frac{33}{40}[/latex]
Money left = 1 - [latex]x \frac{33}{40} = x \frac{7}{40}[/latex] = 1400
x = 8000
i.e, Money spent on food
= [latex] \frac{3}{10}[/latex]* 8000 = 2400
3. A sum of Rs. 312 was divided among 60 boys and some girls in such a way that each boy gets Rs.3.60 and each girl Rs. 2.40. The number of girls is
Answer - Option B
Explanation -
No. of girls
[latex]\frac{3{\frac {3}{2}} - 60 * 3.6}{2.4}[/latex] = 40
4. Some students planned a trip. The budget for food was Rs. 500 But, 5 of them failed to go and thus the cost of food for each member increased by Rs.5. How many students attended the trip ?
Answer - Option B
Explanation -
Let the no. of students initially = x
According to question [latex]\frac{\frac{500}{x - 5}}{\frac {500}{x}}[/latex] = 5
x = 25
No. of students who attended the trip = x – 5 = 20
5. In a class, there are two sections A and B. I f 10 students of section B shift over to section A, the strength of A becomes three times the strength of B. But, if 10 students shift over from A to B, both A and B are equal in strength. How many students are there in sections A and B ?
A. 50 and 30
B. 45 and 15
C. 90 and 40
D. 80 and 40
Answer - Option A
Explanation -
Let the no. of students in class A = x
Let the no. of students in class B = y
According to question
(x + 10) = 3(y – 10) … (i)
also (x – 10) = y + 10 … (ii)
Solving eq. (i) and (ii), we get
x = 50 and y = 30
6. Six persons went to a hotel for meals. Five of them spent Rs. 32 each on their meals while the [latex]{6}^{th}[/latex] person spent Rs. 80 more than the average expenditure of all the six. Total money spent by all the persons is :
A. Rs. 192
B. Rs. 240
C. Rs. 288
D. Rs. 336
Answer - Option C
Explanation -
Let avg expenditure be x.
i.e, x = [latex]\frac{32 * 5 + (80 + 2)}{6}[/latex]
x = 48
i.e, Total money spent = (32 × 5) + (80 + 48)
= 288
7. X is 40 years old and Y is 60 years old How many years ago was the ratio of their ages 3:5
A. 5 years
B. 10 years
C. 20 years
D. 37 years
Answer - Option B
Explanation -
According to question,
[latex]\frac{40 - k}{60 - k}[/latex] = [latex]\frac{3}{5}[/latex]
k = 10 years
8. Rs. 680 is divided among A, B, C such that A gets [latex]\frac{2}{3}[/latex] of what B gets and B gets [latex]\frac{1}{4}[/latex] of what C gets. Then their shares are respectively
A. Rs. 75, Rs. 325, Rs. 280
B. Rs. 80, Rs. 120, Rs. 480
C. Rs. 90, Rs. 210, Rs. 380
D. Rs. 100, Rs. 200, Rs. 380
Answer - Option B
Explanation -
According to question,
[latex]A = \frac{2B}{3}[/latex]
[latex]B =\frac{3A}{2}[/latex]
and [latex]B = \frac{1C}{4}[/latex]
C = 4B = 4[latex]\frac{3A}{2}[/latex]
C = 6A
Now A + B + C = 680
A + [latex]\frac{3A}{2}[/latex]+ 6A = 680
i.e, A = 80
i.e, B = 120
i.e, C = 480
9. X. Y and Z start a business X invests 3 times as much as Y invests and Y invests [latex]\frac{2}{3}[/latex]rd of what Z invests. Then the ratio of capitals of X. Y, Z is 3
A. 3 : 9 : 2
B. 6 : 10 : 15
C. 5 : 3 : 2
D. 6 : 2 : 3
Answer - Option D
Explanation -
According to question, x = 3y
x : y = [latex]\frac{3}{1} * \frac{2}{2} * \frac{6}{2}[/latex]
y = [latex] z \frac{2}{3}[/latex]
y : x = 2 : 3
x : y = 6 : 2
x : y : z = 6 : 2 : 3
10. Entry fee to an exhibition was Rs.80. Later, this was reduced by 25% which increased the sale by 20%. The percentage increased in the number of visitors is
Answer - Option C
Explanation -
Entry fee × No. of visitors = sales.
Multiplying factor = [latex]\frac{3}{4} * x = \frac{6}{5}[/latex]
x = [latex]\frac{8}{5}[/latex] = 1 + [latex]\frac{3}{5}[/latex] = increase of [latex]\frac{3}{5}[/latex] in no. of persons
60 % increase
11. If a : b = 8 : 15 , b : c = 5 : 8 and c : d = 4 : 5, then b : d is
A. 1 : 2
B. 1 : 3
C. 4 : 15
D. 5 : 8
Answer - Option A
Explanation -
[latex]\frac{a}{b}[/latex] = [latex]\frac{8}{15}[/latex];[latex]\frac{b}{c}[/latex] = [latex]\frac{5}{8}[/latex];[latex]\frac{c}{d}[/latex] = [latex]\frac{4}{5}[/latex];
[latex]\frac{a}{b}[/latex] * [latex]\frac{c}{d}[/latex] = [latex]\frac{8}{15}[/latex] * [latex]\frac{4}{5}[/latex] = [latex]\frac{1}{2}[/latex]
12. A person gave [latex]\frac{1}{5}[/latex] part his income to his son and 40 % part of his income to his daughter. He lent out the remaining money in three trusts A, B and C in the ratio of 5 : 3 : 2. I f the difference between the amount got by son and daughter is Rs. 50,000, how much amount did he invest in trust B?
A. Rs. 20000
B. Rs. 30000
C. Rs. 40000
D. Rs. 50000
Answer - Option B
Explanation -
Amount received by son = 20%
Amount received by daughter = 40%
Amount given to trust = 40 %
Difference = 20% is Rs. 50,000
40% = Rs. 1,00,000.
A : B : C = 5 : 3 : 2
B gets [latex]\frac{3}{10}[/latex] * 1,00,000 = Rs. 30,000
13. Two alloys A and B contain zinc and copper in the ratio 5 : 6 and 7 : 8 respectively. If equal quantities of alloys are melted to form a third alloys C, then the ratio of copper and zinc in C will be
A. 76 : 89
B. 89 : 76
C. 48 : 35
D. 35 : 48
Answer - Option B
Explanation -
Let quantity of alloy A = x
Let quantity of alloy B = y
Zinc in alloy (A + B) = [latex]\frac{5x}{11}[/latex] + [latex]\frac{7y}{15}[/latex]
copper in alloy (A + B) = [latex]\frac{6x}{11}[/latex] + [latex]\frac{8x}{15}[/latex]
[latex]\frac{Copper in C}{Zinc in C}[/latex] = [latex]\frac{\frac{6x}11{} + \frac{8x}{15}}{\frac{5x}{11} + \frac{7y}{15}}[/latex] = [latex]\frac{89}{76}[/latex]
i.,e x = y (quantities are same)
14. If A : B = 2 : 3, B : C = 5 : 6 and C : D 8 : 9, then A : D is
A. 2 : 9
B. 20 : 81
C. 20 : 27
D. 40 : 81
Answer - Option D
Explanation -
[latex]\frac{A}{B}[/latex] = [latex]\frac{2}{3}[/latex],[latex]\frac{B}{C}[/latex] = [latex]\frac{5}{6}[/latex], [latex]\frac{C}{D}[/latex] = [latex]\frac{8}{9}[/latex]
[latex]\frac{A}{B}[/latex] * [latex]\frac{B}{C}[/latex] * [latex]\frac{C}{D}[/latex] = [latex]\frac{2}{3}[/latex] * [latex]\frac{5}{6}[/latex] * [latex]\frac{8}{9}[/latex]
[latex]\frac{A}{D}[/latex] = [latex]\frac{40}{81}[/latex]
15. A sum of Rs.16500 is to be divided among A, B, C and D in such a way that the ratio of shares of A and B is 3:4, that of B and C is 1:3 and that of C and D is 6:7. Sum of shares of A and D is
A. Rs.8000
B. Rs.7500
C. Rs.8500
D. Rs.9000
Answer - Option C
Explanation -
A : B : C = 3 : 4 : 12
C : D = 12 : 14
A : B : C : D = 3 : 4 : 12 : 14
sum of shares of A and D is [latex]\frac{3 + 14}{33}* 16500[/latex] = 8500