Lucy had 17 more biscuits than Shiyun at first. After Lucy ate 5 biscuits, she had five times as many biscuits as Shiyun in the end. How many biscuits did Shiyun have?
| |
Shiyun |
Lucy |
| Before |
1 u |
1 u + 17 |
| Change |
|
- 5 |
| After |
1 u |
1 u + 12 |
Comparing Shiyun
and Lucy in the end |
1 u |
5 u |
The number of biscuits that Shiyun had remains unchanged.
Number of biscuits that Lucy had in the end
= 5 x 1 u
= 5 u
5 u = 1 u + 12
5 u - 1 u = 12
4 u = 12
1 u = 12 ÷ 4 = 3
Number of biscuits that Shiyun had
= 1 u
= 3
Answer(s): 3
