A and B rent a pasture for 12 months. A puts in 70 cows for 9 months. How many cows can B put in for the remaining 3 months if he pays half as much rent as A?
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → 105
Rent of a pasture is shared in the ratio of cows × months (cow-months), just as profit is shared in the ratio of capital × time. B pays half of A’s rent, so he may use half of A’s cow-months.
A’s cow-months \(=70\times9=630\)
B’s cow-months \(\displaystyle =\frac{630}{2}=315\)
B grazes for 3 months, so the number of cows \(\displaystyle =\frac{315}{3}=105\)
B can put in 105 cows.