Tiny Totts Is a Nursery School for Kindergarten Children

Multiple Choice

Tiny Totts is a nursery school for kindergarten children. When there are twenty children enrolled, total revenues and total costs are $6,000 and $3,200, respectively. When there are twenty-one children enrolled, total revenues and total costs are $6,300 and $3,255, respectively. The average cost when there are twenty children enrolled in the school is:

A) $55.
B) $160.
C) $162.75.
D) $300
E) $315.