The average cost of 7 books is $40.
After 2 books are removed,
the average cost of the remaining books is $30.
- What is the total cost of the 2 books that are removed?
- What is the average cost of the 2 books that are removed?
(a)
Total cost of 7 books
= 7 x 40
= $280
Number of remaining books
= 7 - 2
= 5
Total cost of the remaining books
= 5 x 30
= $150
Total cost of the 2 books that are removed
= 280 - 150
= $130
(b)
Average cost of the 2 books that are removed
= 130 ÷ 2
= $65
Answer(s): (a) $130; (b) $65