Esther had some kiwi and starfruit face masks.
15 of them were kiwi. She gave away
13 of the kiwi face masks and
13 of the starfruit face masks. In the end, she had 30 kiwi and starfruit face masks altogether. How many starfruit face masks did Esther have at first?
| |
Kiwi face masks |
Starfruit face masks |
Total |
Comparing kiwi and starfruit face masks
at first |
1x3 =
3 u |
4x3 =
12 u |
5x3 =
15 u |
Before |
3 u |
3x4 =
12 u |
|
Change |
- 1 u |
- 1x4 =
- 4 u |
|
After |
2 u |
2x4 =
8 u |
|
The number of starfruit face masks at first is repeated. Make the number of starfruit face masks the same. LCM of 4 and 3 is 12.
Total number of face masks in the end
= 2 u + 8 u
= 10 u
10 u = 30
1 u = 30 ÷ 10 = 3
Number of starfruit masks at first
= 12 u
= 12 x 3
= 36
Answer(s): 36
