A. Rs. 4000

B. Rs. 4200

C. Rs. 4400

D. Rs. 4800

### Solution(By Apex Team)

Let a, b, and c be the annual incomes of Ramesh, Suresh, and Pratap, respectively. Now, we are given that The arithmetic mean of the annual incomes of Ramesh and Suresh was Rs. 3800. Hence, $\begin{array}{l}\Large\frac{a+b}{2}=\small3800\\ \Rightarrow a+b=2\times3800=7600\end{array}$ The arithmetic mean of the annual incomes of Suresh and Pratap was Rs. 4800. Hence, $\begin{array}{l}\Large\frac{b+c}{2}=\small4800\\ \Rightarrow b+c=2\times4800=9600\end{array}$ The arithmetic mean of the annual incomes of Pratap and Ramesh was Rs. 5800. Hence, $\begin{array}{l}\Large\frac{c+a}{2}=\small5800\\ \Rightarrow c+a=2\times5800=11,600\end{array}$ Adding these three equations yields: (a + b) + (b + c) + (c + a) = 7600 + 9600 + 11,600 2a + 2b + 2c = 28,800 a + b + c = 14,400 The average of the incomes of the three equals the sum of the incomes divided by 3, $\begin{array}{c}\Large\frac{\mathrm{a}+\mathrm{b}+\mathrm{c}}{3}\\ =\Large\frac{14,400}{3}\\ =\mathrm{Rs}.4800\end{array}$

A. 20
B. 21
C. 28
D. 32

A. 18
B. 20
C. 24
D. 30

A. 10 years
B. 10.5 years
C. 11 years
D. 12 years