Yoko was saving money to buy pens. She saved $3 every 5 days. After saving for 65 days, she went to buy pens that were on sale.
- What was the most number of pens she could buy?
- Yoko wanted to buy 34 pens. How much more did she need to save?
(a)
Number of sets of 5 days
= 65 ÷ 5
= 13
Amount that Yoko saved in 65 days
= 13 x 3
= $39
Maximum number of sets of 6 pens that Yoko could buy
= 39 ÷ 10
= 3 r $9
Remaining amount left after buying sets of 6 pens = $9
Maximum number of sets of 3 pens that Yoko could buy with $9
= 9 ÷ 6
= 1 r $3
Remaining amount left after buying sets of 3 pens = $3
Maximum number of pens that Yoko could buy with $3
= 3 ÷ 3
= 1
Most number of pens that Yoko could buy
= 3 x 6 + 1 x 3 + 1
= 18 + 3 + 1
= 22
(b)
Number of sets of 6 pens that Yoko could buy
= 34 ÷ 6
= 5 r 4
Number of sets of 3 pens that Yoko could buy
= 4 ÷ 3
= 1 r 1
Number of individual pens that Yoko could buy = 1
Amount that Yoko needed to buy 34 pens
= 5 x 10 + 1 x 6 + 3
= 50 + 6 + 3
= $59
Amount that Yoko needed to save more
= 59 - 39
= $20
Answer(s): (a) 22; (b) $20