Betty had some persimmon and mango face masks.
13 of them were persimmon. She gave away
15 of the persimmon face masks and
15 of the mango face masks. In the end, she had 36 persimmon and mango face masks altogether. How many mango face masks did Betty have at first?
| |
Persimmon face masks |
Mango face masks |
Total |
Comparing persimmon and mango face masks
at first |
1x5 =
5 u |
2x5 =
10 u |
3x5 =
15 u |
Before |
5 u |
5x2 =
10 u |
|
Change |
- 1 u |
- 1x2 =
- 2 u |
|
After |
4 u |
4x2 =
8 u |
|
The number of mango face masks at first is repeated. Make the number of mango face masks the same. LCM of 2 and 5 is 10.
Total number of face masks in the end
= 4 u + 8 u
= 12 u
12 u = 36
1 u = 36 ÷ 12 = 3
Number of mango masks at first
= 10 u
= 10 x 3
= 30
Answer(s): 30
