What is the fraction of the pie her sister eat

Question

Maria ate 1/3 of a pie. Her sister eats 1/5 of that. What fraction of the pie did her sister eat

Answer 1

Maria ate 1/3 of the pie, so 1 - 1/3 = 2/3 is left

Her sister eats 1/5 of 2/3:

2/3 * 1/5 = 2/15

Her sister ate 2/15 of the pie.