Gabby baked a total of 386 cookies and muffins. After giving away 80% of the muffins and 90% of the cookies, she was left with four times as many muffins as cookies. Find the number of cookies Gabby gave away.
| |
Muffins |
Cookies |
| Before |
5x4 =
20 u
|
10 u |
| Change |
- 4x4 =
16 u |
- 9 u |
| After |
1x4 =
4 u |
1 u |
Comparing muffins and
cookies in the end |
4x1 =
4 u |
1x1 =
1 u |
80% =
80100 =
4590% =
90100 =
910The number of muffins in the end is the repeated identity. Make the number of muffins in the end the same. LCM of 1 and 4 is 4.
Total number of pastries at first
= 20 u + 10 u
= 30 u
30 u = 386
1 u = 386 ÷ 30 = 6
Number of cookies that Gabby gave away
= 9 u
= 9 x 6
= 54
Answer(s): 54
