Cathy had some kiwi and persimmon face masks.
15 of them were kiwi. She gave away
13 of the kiwi face masks and
13 of the persimmon face masks. In the end, she had 100 kiwi and persimmon face masks altogether. How many persimmon face masks did Cathy have at first?
| |
Kiwi face masks |
Persimmon face masks |
Total |
Comparing kiwi and persimmon 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 persimmon face masks at first is repeated. Make the number of persimmon 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 = 100
1 u = 100 ÷ 10 = 10
Number of persimmon masks at first
= 12 u
= 12 x 10
= 120
Answer(s): 120
