1 sticker costs $3.
For every 10 stickers bought, a discount of $7 is given.
- How much do 10 stickers cost?
- How much do 17 stickers cost?
- How much do 27 stickers cost?
(a)
Cost of every 10 stickers
= 10 x 3 - 7
= 30 - 7
= $23
(b)
Number of stickers that do not belong to a set
= 17 ÷ 10
= 1 r 7
Cost of the 7 extra stickers
= 7 x 3
= $21
Cost of 17 stickers
= 23 + 21
= $44
(c)
Number of sets of 10 stickers
= 27 ÷ 10
= 2 r 7
Cost of 20 stickers
= 2 x 23
= $46
Cost of 7 stickers
= 7 x 3
= $21
Cost of 27 stickers
= 46 + 21
= $67
Answer(s): (a) $23; (b) $44; (c) $67