1 sticker costs $6.
For every 10 stickers bought, a discount of $3 is given.
- How much do 10 stickers cost?
- How much do 15 stickers cost?
- How much do 31 stickers cost?
(a)
Cost of every 10 stickers
= 10 x 6 - 3
= 60 - 3
= $57
(b)
Number of stickers that do not belong to a set
= 15 ÷ 10
= 1 r 5
Cost of the 5 extra stickers
= 5 x 6
= $30
Cost of 15 stickers
= 57 + 30
= $87
(c)
Number of sets of 10 stickers
= 31 ÷ 10
= 3 r 1
Cost of 30 stickers
= 3 x 57
= $171
Cost of 1 stickers
= 1 x 6
= $6
Cost of 31 stickers
= 171 + 6
= $177
Answer(s): (a) $57; (b) $87; (c) $177