Mary and Yen had a total of $520 at first. After Mary spent
14 of her money and Yen spent
23 of her money, they had the same amount of money left.
- How much money did Mary have at first?
- Yen has the same number of $2-notes and $10-notes at first. How many $10-notes did she have at first?
| |
Mary |
Yen |
Total |
Before |
4 u |
3x3 =
9 u |
13 u |
Change |
- 1 u |
- 2x3 =
- 6 u |
|
After |
3 u |
1x3 =
3 u |
|
(a)
The amount that Mary and Yen had in the end is the same. Make the amount that they each had in the end the same. LCM of 1 and 3 is 3.
Total amount that Mary and Yen had at first
= 4 u + 9 u
= 13 u
13 u = 520
1 u = 520 ÷ 13 = 40
Amount that Mary had at first
= 4 u
= 4 x 40
= $160
(b)
Amount that Yen had at first
= 9 u
= 9 x 40
= $360
Yen has the same number of $2-note and $10-note at first.
Value of 1 set of $2-note and $10-note
= 2 + 10
= $12
Number of 2-notes
= 360 ÷ 12
= 30
Answer(s): (a) $160; (b) 30
