The average cost of 5 books is $60.
After 2 new books are added,
the average cost of all the books is $50.
- What is the total cost of the 2 books that are added?
- What is the average cost of the 2 books that are added?
(a)
Total cost of 5 books
= 5 x 60
= $300
Number of books
= 5 + 2
= 7
Total cost of all the books
= 7 x 50
= $350
Total cost of the 2 books that are added
= 350 - 300
= $50
(b)
Average cost of the 2 books that are added
= 50 ÷ 2
= $25
Answer(s): (a) $50; (b) $25