The average cost of 5 guide books is $30.
After a guide book that costs $70 is removed,
- What is new total cost of all the remaining guide books?
- What is new average cost of all the remaining guide books?
(a)
Total cost of 5 guide books
= 5 x 30
= $150
New total cost of all the remaining guide books
= 150 - 70
= $80
(b)
Number of remaining guide books
= 5 - 1
= 4
New average cost of all the remaining guide books
= 80 ÷ 4
= $20
Answer(s): (a) $80; (b) $20