The average cost of 4 dictionaries is $20.
After another dictionary that costs $80 is added,
- What is new total cost of all the dictionaries?
- What is new average cost of all the dictionaries?
(a)
Total cost of 4 dictionaries
= 4 x 20
= $80
New total cost of all the dictionaries
= 80 + 80
= $160
(b)
New total number of dictionaries
= 4 + 1
= 5
New average cost of all the dictionaries
= 160 ÷ 5
= $32
Answer(s): (a) $160; (b) $32