Vincent had an equal number of strawberry cupcakes, blueberry cupcakes and butter cupcakes. After he ate 39 strawberry cupcakes, some blueberry cupcakes and butter cupcakes, there were 80 cupcakes left. The number of blueberry cupcakes he ate was thrice the number of butter cupcakes he ate. The number of blueberry cupcakes left was 24 more than the number of strawberry cupcakes left. How many strawberry cupcakes were there at first?
| |
Strawberry cupcakes |
Blueberry cupcakes |
Butter cupcakes |
Total cupcakes |
| Before |
1 p + 39 |
1 p + 3 u + 24 |
1 p + 3 u + 24 |
|
| Change |
- 39 |
- 3 u |
- 1 u |
|
| After |
1 p |
1 p + 24 |
1 p + 24 + 1 u |
80 |
Number of blueberry cupcakes and strawberry cupcakes was equal at first.
1 p + 3 u + 24 = 1 p + 39
3 u = 39 - 24
3 u = 15
1 u = 15 ÷ 3 = 5
Total number of cupcakes in the end
= 1 p + 1 p + 24 + 1 p + 24 + 5
= 1 p + 1 p + 1 p + 24 + 24 + 5
= 3 p + 53
3 p + 53 = 80
3 p = 80 - 53
3 p = 27
1 p = 27 ÷ 3 = 9
Number of strawberry cupcakes at first
= 1 p + 39
= 9 + 39
= 48
Answer(s): 48
