Opal and Hilda had a total of $810 at first. After Opal spent
13 of her money and Hilda spent
23 of her money, they had the same amount of money left.
- How much money did Opal have at first?
- Hilda has the same number of $10-notes and $5-notes at first. How many $5-notes did she have at first?
| |
Opal |
Hilda |
Total |
Before |
3 u |
3x2 =
6 u |
9 u |
Change |
- 1 u |
- 2x2 =
- 4 u |
|
After |
2 u |
1x2 =
2 u |
|
(a)
The amount that Opal and Hilda had in the end is the same. Make the amount that they each had in the end the same. LCM of 1 and 2 is 2.
Total amount that Opal and Hilda had at first
= 3 u + 6 u
= 9 u
9 u = 810
1 u = 810 ÷ 9 = 90
Amount that Opal had at first
= 3 u
= 3 x 90
= $270
(b)
Amount that Hilda had at first
= 6 u
= 6 x 90
= $540
Hilda has the same number of $10-note and $5-note at first.
Value of 1 set of $10-note and $5-note
= 10 + 5
= $15
Number of 10-notes
= 540 ÷ 15
= 36
Answer(s): (a) $270; (b) 36
