Abi was saving money to buy pens. She saved $3 every 7 days. After saving for 126 days, she went to buy pens that were on sale.
- What was the most number of pens she could buy?
- Abi wanted to buy 44 pens. How much more did she need to save?
(a)
Number of sets of 7 days
= 126 ÷ 7
= 18
Amount that Abi saved in 126 days
= 18 x 3
= $54
Maximum number of sets of 8 pens that Abi could buy
= 54 ÷ 11
= 4 r $10
Remaining amount left after buying sets of 8 pens = $10
Maximum number of sets of 4 pens that Abi could buy with $10
= 10 ÷ 6
= 1 r $4
Remaining amount left after buying sets of 4 pens = $4
Maximum number of pens that Abi could buy with $4
= 4 ÷ 4
= 1
Most number of pens that Abi could buy
= 4 x 8 + 1 x 4 + 1
= 32 + 4 + 1
= 37
(b)
Number of sets of 8 pens that Abi could buy
= 44 ÷ 8
= 5 r 4
Number of sets of 4 pens that Abi could buy
= 4 ÷ 4
= 1 r 0
Amount that Abi needed to buy 44 pens
= 5 x 11 + 1 x 6
= 55 + 6
= $61
Amount that Abi needed to save more
= 61 - 54
= $7
Answer(s): (a) 37; (b) $7