Q.Ram is twice as fast as Aman and Aman is thrice as fast as Rohit in doing a work. Working together they can finish the work in 10 days. In how many days can Aman and Rohit together finish the work.
A.15
B.20
C. 25
D. 27
E. 32
Answer: 25 Days
Solution:
Let the Rohit one day work be ‘x’
Aman’s one day work be ‘3x’
Ram’s one day work be ‘6x’
Therefore, three can do this particular work together = 1/10
\begin{array}{l} \therefore x+3 x+6 x=\frac{1}{10} \\ \Rightarrow 10 x=\frac{1}{10} \\ \therefore x=\frac{1}{100} \end{array}
So, Aman and Rohit can do this work is 3x+x=1/100+1/100
\begin{array}{l} \Rightarrow 3x+x=\frac{1}{100} \\ \Rightarrow 4x=\frac{1}{100} \\ \therefore x=25 \text { Days } \end{array}
Hence, Aman and Rohit can do this work in 25 days