In a factory, 20 people can make 20 toys in 15 days working 10 hours per day. Then, in how many days can 25 persons make 30 toys working 20 hours per day?

Question: In a factory, 20 people can make 20 toys in 15 days working 10 hours per day. Then, in how many days can 25 persons make 30 toys working 20 hours per day?

Solution:
Here,
M₁ = 20, M₂ = 25
D₁ = 15, D₂ = ?
T₁ = 10, T₂ = 20,
W₁ = 20 and W₂ = 30.

We know,
M₁ × D₁ × T₁ × W₂ = M₂ × D₂ × T₂ × W₁
⇒ 20 × 15 × 10 × 30 = 25 × D₂ × 20 × 20
∴ D₂ = 9

Thus, the required day = 9 days