Question

There are currently 417 students enrolled in Webster Elementary School, and the number of students is decreasing at the rate of 15 students per year. Currently the annual expense to educate one student is $1,149, and the expense to educate one student is increasing at the rate of $39 per year. Use the product rule to determine the rate at which the total expense to educate the students at Webster Elementary School is currently changing per year.

Answer 1

Current student = 417

Student increasing rate per year = 15

Annual cost to educate one student = $1,149

The decreasing rate on one student = $39

Total decreasing cost = 417*$39 = $16,263

Total cost of Increase students per year = 15 * $1,149 = $17,235

∴$17,235 - $16,263 = $972

So, the cost to educate the students at Webster Elementary School is increasing at the rate of $972 per year.