Zoe baked a total of 372 cupcakes and cookies. After giving away 90% of the cookies and 80% of the cupcakes, she was left with thrice as many cookies as cupcakes. Find the number of cupcakes Zoe gave away.
| |
Cookies |
Cupcakes |
| Before |
10x3 =
30 u
|
5 u |
| Change |
- 9x3 =
27 u |
- 4 u |
| After |
1x3 =
3 u |
1 u |
Comparing cookies and
cupcakes in the end |
3x1 =
3 u |
1x1 =
1 u |
90% =
90100 =
91080% =
80100 =
45The number of cookies in the end is the repeated identity. Make the number of cookies in the end the same. LCM of 1 and 3 is 3.
Total number of pastries at first
= 30 u + 5 u
= 35 u
35 u = 372
1 u = 372 ÷ 35 = 6
Number of cupcakes that Zoe gave away
= 4 u
= 4 x 6
= 24
Answer(s): 24
