By grouping:
Every big monk eats three and every little monk eats one. We regard 1 big monk and three little monks as four people and 1 group, so 100 monks are divided into:
100÷4=25 groups
Because there are 1 big monks in each group, the number of big monks is: 1×25=25.
The number of young monks is: 100-25=75.
A: Yes. . . . . .