1 sticker costs $4.
For every 10 stickers bought, a discount of $3 is given.
- How much do 10 stickers cost?
- How much do 13 stickers cost?
- How much do 23 stickers cost?
(a)
Cost of every 10 stickers
= 10 x 4 - 3
= 40 - 3
= $37
(b)
Number of stickers that do not belong to a set
= 13 ÷ 10
= 1 r 3
Cost of the 3 extra stickers
= 3 x 4
= $12
Cost of 13 stickers
= 37 + 12
= $49
(c)
Number of sets of 10 stickers
= 23 ÷ 10
= 2 r 3
Cost of 20 stickers
= 2 x 37
= $74
Cost of 3 stickers
= 3 x 4
= $12
Cost of 23 stickers
= 74 + 12
= $86
Answer(s): (a) $37; (b) $49; (c) $86