Question Detail
Find the fourth proportion to 2,3,6
- 18
- 12
- 9
- 4
Answer: Option C
Explanation:
2:3 :: 6:x
=> 2/3 = 6/x
=> x = 18/2
=> x = 9
1. Salaries of Ravi and Sumit are in the ratio 2:3. If the salary of each is increased by Rs 4000, the new ratio becomes 40:57. What is Sumit present salary.
- 32000
- 34000
- 38000
- 40000
Answer: Option C
Explanation:
Let the original Salaries of Ravi and Sumit is 2x and 3x.
So as per question
\begin{aligned}
\frac{2x+4000}{3x+4000} = \frac{40}{57} \\
=> 57(2x+4000) = 40(3x+4000) \\
=> 6x = 68000 \\
=> 3x = 34000 \\
\text{ Sumit Salary =} 3x+4000 \\
34000 + 4000 = 38000
\end{aligned}
2. Find the fourth proportion to 2,3,6
- 18
- 12
- 9
- 4
Answer: Option C
Explanation:
2:3 :: 6:x
=> 2/3 = 6/x
=> x = 18/2
=> x = 9
3. If a:b = 2:3 and b:c = 4:3, then find a:b:c
- 8:12:9
- 2:3:8
- 2:3:9
- 2:3:12
Answer: Option A
Explanation:
\begin{aligned}
a:b = 2:3 \\
b:c = 4:3 = (4*\frac{3}{4} : 3*\frac{3}{4}) \\
= 3:\frac{9}{4} \\
a:b:c = 2:3:\frac{9}{4} \\
= 8:12:9
\end{aligned}
4. If A:B:C = 2:3:4, then find
\begin{aligned}
\frac{A}{B}:\frac{B}{C}:\frac{C}{A}
\end{aligned}
- 5:9:24
- 6:9:24
- 7:9:24
- 8:9:24
Answer: Option D
Explanation:
Let A = 2x, B = 3x, C = 4x, then,
\begin{aligned}
\frac{A}{B} = \frac{2x}{3x} = \frac{2}{3} \\
\frac{B}{C} = \frac{3x}{4x} = \frac{3}{4} \\
\frac{C}{A} = \frac{4x}{2x} = \frac{2}{1} \\
=> \frac{A}{B}:\frac{B}{C}:\frac{C}{A} \\
= \frac{2}{3}:\frac{3}{4}:\frac{2}{1} \\
= 8:9:24
\end{aligned}
5. There are two numbers and their ratio is 3 : 9. If we substract 9 from both numbers then their ratio becomes 12 : 13, what is value is smaller number ?
- 23
- 27
- 31
- 33
Answer: Option D
Explanation:
From question, lets assume that two numbers are 3x and 5x.
\begin{aligned}
\text{then, }\frac{3x - 9}{ 5x - 9} = \frac{12}{23}\\
=> \text{23(3x - 9) = 12(5x - 9)}\\
=> 9x = 99 \\
=> x = 11
\end{aligned}
So numbers are 3(11) = 33, 5(11) = 55.
Smaller number is 33.