The ratio of salaries of P and Q last year is 4 : 5. The ratio of last year salary and the present salary of P is 3 : 5 and for Q this ratio is 2 : 3.
If their total salary at present is Rs. 6800, what is salary of Q ?

Correct option is D

Given:
Ratio of salaries of P and Q last year = 4 : 5
Ratio of last year salary and present salary of P = 3 : 5
Ratio of last year salary and present salary of Q = 2 : 3
Total present salary of P and Q = Rs. 6800

Solution:

Let last year salary of P = 4x and last year salary of Q = 5x
Present salary of P = $$\frac{ 5}{3}\times4x$$​​
Present salary of Q = $$\frac{3}{2}\times 5x$$​

Total present salary = Present salary of P + Present salary of Q

Let last year salary of P = 4x
Let last year salary of Q = 5x
Present salary of P = $$\frac{5}{3}\times 4x = \frac{20}{3}x$$​​

Present salary of Q = $$\frac{ 3}{2}\times{ 5x} = \frac{15}{2}x$$​​
Total present salary = $$\frac{20}{3}x +\frac{15}{2}x = 6800:$$​​
​$$\frac{(20x)}{3 }+ \frac{(15x)}{2} = 6800\\\ \\\frac{40x}{6}+ \frac{45x}{6} = 6800\\\ \\\frac{85x}{6} = 6800$$​​
85x = 40800
x = 480
Present salary of Q:
​$$\frac{15}{2} \times{ 480 }= 3600$$​​

Therefore, the present salary of Q is Rs. 3600.