The average cost of 6 books is $60.
After 4 books are removed,
the average cost of the remaining books is $30.
- What is the total cost of the 4 books that are removed?
- What is the average cost of the 4 books that are removed?
(a)
Total cost of 6 books
= 6 x 60
= $360
Number of remaining books
= 6 - 4
= 2
Total cost of the remaining books
= 2 x 30
= $60
Total cost of the 4 books that are removed
= 360 - 60
= $300
(b)
Average cost of the 4 books that are removed
= 300 ÷ 4
= $75
Answer(s): (a) $300; (b) $75