The average cost of 3 paperbacks is $20.
After another paperback that costs $80 is added,
- What is new total cost of all the paperbacks?
- What is new average cost of all the paperbacks?
(a)
Total cost of 3 paperbacks
= 3 x 20
= $60
New total cost of all the paperbacks
= 60 + 80
= $140
(b)
New total number of paperbacks
= 3 + 1
= 4
New average cost of all the paperbacks
= 140 ÷ 4
= $35
Answer(s): (a) $140; (b) $35