1 marble costs $5.
For every 10 marbles bought, a discount of $6 is given.
- How much do 10 marbles cost?
- How much do 16 marbles cost?
- How much do 26 marbles cost?
(a)
Cost of every 10 marbles
= 10 x 5 - 6
= 50 - 6
= $44
(b)
Number of marbles that do not belong to a set
= 16 ÷ 10
= 1 r 6
Cost of the 6 extra marbles
= 6 x 5
= $30
Cost of 16 marbles
= 44 + 30
= $74
(c)
Number of sets of 10 marbles
= 26 ÷ 10
= 2 r 6
Cost of 20 marbles
= 2 x 44
= $88
Cost of 6 marbles
= 6 x 5
= $30
Cost of 26 marbles
= 88 + 30
= $118
Answer(s): (a) $44; (b) $74; (c) $118