1 sticker costs $9.
For every 10 stickers bought, a discount of $5 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 9 - 5
= 90 - 5
= $85
(b)
Number of stickers that do not belong to a set
= 13 ÷ 10
= 1 r 3
Cost of the 3 extra stickers
= 3 x 9
= $27
Cost of 13 stickers
= 85 + 27
= $112
(c)
Number of sets of 10 stickers
= 23 ÷ 10
= 2 r 3
Cost of 20 stickers
= 2 x 85
= $170
Cost of 3 stickers
= 3 x 9
= $27
Cost of 23 stickers
= 170 + 27
= $197
Answer(s): (a) $85; (b) $112; (c) $197