Xuan had 15 more cupcakes than Emma at first. After Xuan ate 3 cupcakes, she had four times as many cupcakes as Emma in the end. How many cupcakes did Emma have?
| |
Emma |
Xuan |
| Before |
1 u |
1 u + 15 |
| Change |
|
- 3 |
| After |
1 u |
1 u + 12 |
Comparing Emma
and Xuan in the end |
1 u |
4 u |
The number of cupcakes that Emma had remains unchanged.
Number of cupcakes that Xuan had in the end
= 4 x 1 u
= 4 u
4 u = 1 u + 12
4 u - 1 u = 12
3 u = 12
1 u = 12 ÷ 3 = 4
Number of cupcakes that Emma had
= 1 u
= 4
Answer(s): 4
