The average cost of 4 textbooks is $50.
After a textbook that costs $80 is removed,
- What is new total cost of all the remaining textbooks?
- What is new average cost of all the remaining textbooks?
(a)
Total cost of 4 textbooks
= 4 x 50
= $200
New total cost of all the remaining textbooks
= 200 - 80
= $120
(b)
Number of remaining textbooks
= 4 - 1
= 3
New average cost of all the remaining textbooks
= 120 ÷ 3
= $40
Answer(s): (a) $120; (b) $40