1 bead costs $9.
For every 10 beads bought, a discount of $4 is given.
- How much do 10 beads cost?
- How much do 12 beads cost?
- How much do 31 beads cost?
(a)
Cost of every 10 beads
= 10 x 9 - 4
= 90 - 4
= $86
(b)
Number of beads that do not belong to a set
= 12 ÷ 10
= 1 r 2
Cost of the 2 extra beads
= 2 x 9
= $18
Cost of 12 beads
= 86 + 18
= $104
(c)
Number of sets of 10 beads
= 31 ÷ 10
= 3 r 1
Cost of 30 beads
= 3 x 86
= $258
Cost of 1 beads
= 1 x 9
= $9
Cost of 31 beads
= 258 + 9
= $267
Answer(s): (a) $86; (b) $104; (c) $267