Answer:
His brother ate 1/15 of banana cream less than his sister.
Explanation:
It is given that:
Ubi's brother ate 1/3 of the pie and his sister ate 2/5 of the pie.
In order to find the amount his brother ate less than this sister is:
Amount eaten by his sister-Amount eaten by his brother.

( since, the denominators of the two fractions are different.
Hence, we take the least common multiple of the two denominators )
