Gillian and Ivory had an equal number of mochi balls. After Gillian bought another 20 mochi balls and Ivory bought another 4 mochi balls, Gillian had thrice as many mochi balls as Ivory. Find the number of mochi balls that each of them had at first.
| |
Gillian |
Ivory |
| Before |
3 u - 20 |
1 u - 4 |
| Change |
+ 20 |
+ 4 |
| After |
3 u |
1 u |
The number of mochi balls that Gillian and Ivory had at first is the same.
3 u - 20 = 1 u - 4
3 u - 1 u = 20 - 4
2 u = 16
1 u = 16 ÷ 2 = 8
Number of mochi balls that each had at first
= 8 - 4
= 4
Answer(s): 4
