If 15 boys earn Rs.900 in 5 days, how much will 20 boys earn in 7 days ?

Explanation

To solve the problem step by step, we can use the concept of work done by boys in terms of days and earnings.

### Step 1: Determine the daily earnings of 15 boys
We know that 15 boys earn Rs. 900 in 5 days. To find out how much they earn in one day, we can divide the total earnings by the number of days.

\[ \text{Daily earnings of 15 boys} = \frac{900}{5} = 180 \text{ Rs.} \]
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