1 bead costs $9.
For every 10 beads bought, a discount of $7 is given.
- How much do 10 beads cost?
- How much do 18 beads cost?
- How much do 32 beads cost?
(a)
Cost of every 10 beads
= 10 x 9 - 7
= 90 - 7
= $83
(b)
Number of beads that do not belong to a set
= 18 ÷ 10
= 1 r 8
Cost of the 8 extra beads
= 8 x 9
= $72
Cost of 18 beads
= 83 + 72
= $155
(c)
Number of sets of 10 beads
= 32 ÷ 10
= 3 r 2
Cost of 30 beads
= 3 x 83
= $249
Cost of 2 beads
= 2 x 9
= $18
Cost of 32 beads
= 249 + 18
= $267
Answer(s): (a) $83; (b) $155; (c) $267