1 bead costs $3.
For every 10 beads bought, a discount of $7 is given.
- How much do 10 beads cost?
- How much do 13 beads cost?
- How much do 27 beads cost?
(a)
Cost of every 10 beads
= 10 x 3 - 7
= 30 - 7
= $23
(b)
Number of beads that do not belong to a set
= 13 ÷ 10
= 1 r 3
Cost of the 3 extra beads
= 3 x 3
= $9
Cost of 13 beads
= 23 + 9
= $32
(c)
Number of sets of 10 beads
= 27 ÷ 10
= 2 r 7
Cost of 20 beads
= 2 x 23
= $46
Cost of 7 beads
= 7 x 3
= $21
Cost of 27 beads
= 46 + 21
= $67
Answer(s): (a) $23; (b) $32; (c) $67