The average cost of 6 textbooks is $40.
After a textbook that costs $70 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 6 textbooks
= 6 x 40
= $240
New total cost of all the remaining textbooks
= 240 - 70
= $170
(b)
Number of remaining textbooks
= 6 - 1
= 5
New average cost of all the remaining textbooks
= 170 ÷ 5
= $34
Answer(s): (a) $170; (b) $34