A Little Homework Help

An elementary school teacher decides to poll the class on the difficulty
of last night's homework assignment.

"How many people were able to complete the assignment without parent's
help?" About 25% of the class raises their hands.

"How many people were able to complete the assignment with the help of a
parent?" About 70% of the class raises their hands.

The teacher still notices about 5% of the class did not raise their
hands. She then calls out, "How many people had to help a parent
complete your assignment?"