30 workers earn ₹600 a day on average. Skilled workers earn ₹800 and unskilled workers ₹500. How many are skilled?

Explanation

1. 01

   Unskilled : skilled $= (800 - 600) : (600 - 500) = 200 : 100 = 2 : 1$.

2. 02

   Skilled workers are $\frac{1}{3} \times 30 = 10$.