The average cost of 4 books is $50.
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 4 books
= 4 x 50
= $200
Number of remaining books
= 4 - 2
= 2
Total cost of the remaining books
= 2 x 30
= $60
Total cost of the 2 books that are removed
= 200 - 60
= $140
(b)
Average cost of the 2 books that are removed
= 140 ÷ 2
= $70
Answer(s): (a) $140; (b) $70