Xylia was saving money to buy pens. She saved $4 every 8 days. After saving for 88 days, she went to buy pens that were on sale.
- What was the most number of pens she could buy?
- Xylia wanted to buy 51 pens. How much more did she need to save?
(a)
Number of sets of 8 days
= 88 ÷ 8
= 11
Amount that Xylia saved in 88 days
= 11 x 4
= $44
Maximum number of sets of 9 pens that Xylia could buy
= 44 ÷ 9
= 4 r $8
Remaining amount left after buying sets of 9 pens = $8
Maximum number of sets of 5 pens that Xylia could buy with $8
= 8 ÷ 6
= 1 r $2
Remaining amount left after buying sets of 5 pens = $2
Maximum number of pens that Xylia could buy with $2
= 2 ÷ 2
= 1
Most number of pens that Xylia could buy
= 4 x 9 + 1 x 5 + 1
= 36 + 5 + 1
= 42
(b)
Number of sets of 9 pens that Xylia could buy
= 51 ÷ 9
= 5 r 6
Number of sets of 5 pens that Xylia could buy
= 6 ÷ 5
= 1 r 1
Number of individual pens that Xylia could buy = 1
Amount that Xylia needed to buy 51 pens
= 5 x 9 + 1 x 6 + 2
= 45 + 6 + 2
= $53
Amount that Xylia needed to save more
= 53 - 44
= $9
Answer(s): (a) 42; (b) $9