4 goats or 6 sheep can graze a field in 50 days

• Time Work

4 goats or 6 sheep can graze a field in 50 days. 2 goats and 9 sheep can graze a field in

1. 100 days
2. 75 days
3. 50 days
4. 25 days

Answer

1 day's work or efficiency of 4 goats = 1/50 = 2%

So, efficiency of 1 goat = 2/4 % = 0.5% 

Similarly efficiency of 1 sheep = 2/6 % = 1/3%

Therefore efficiency of 2 goats and 9 sheep = 2×(0.5 %) + 9×(1/3 %) = 1% + 3% = 4%

So, time taken = 100 / 4 = 25 days

The correct option is D.