Mary has 400 sheep on her farm. She gave a quarter of her sheep to her sister, and half of the remaining sheep to her brother. How many sheep remain with Mary?
Let's think step by step below.
150
Mary gives 1 / 4 * 400 = 100 sheep to her sister.

She now has 400 - 100 = 300 sheep remaining.

She then gives 1 / 2 * 300 = 150 sheep to her brother.

So 300 - 150 = 150 sheep remain.

.

The final answer: 150