The salaries of A, B and C are of ratio 2:3:5. If the increments of 15%, 10% and 20% are done to their respective salaries, then find the new ratio of their salaries.

Answer: Option D

Explanation:

Let A salary be 2k
B salary be 3k and C salary be 5k

\begin{aligned}
\text{A's new salary = }\frac{115}{100}*2k \\
= \frac{23}{10}k \\
\text{B's new salary = }\frac{110}{100}*3k \\
= \frac{33}{10}k \\
\text{C's new salary = }\frac{120}{100}*5k \\
= 6k \\

\text{New ratio = }\\
\frac{23k}{10}:\frac{33k}{10}:6k \\
= 23:33:60 \\
\end{aligned}

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.

Answer: Option B

Explanation:

Let the boy are 8x and Girls are 5x

=> 5x = 200
=> x = 40

Total students = 8x+5x = 13x = 13(40) = 520

Answer: Option B

Explanation:

\begin{aligned}
\frac{1}{2}:\frac{2}{3}:\frac{3}{4} \\
= 6:8:9\\
\text{First part =} 782 * \frac{6}{23} \\
= 204
\end{aligned}

Answer: Option D

Explanation:

Quantity of Milk = 60*(2/3) = 40 liters
Quantity of water = 60-40 = 20 liters

As per question we need to add water to get quantity 2:1

=> 40/(20+x) = 1/2
=> 20 + x = 80
=> x = 60 liters