Kimberly baked a total of 441 cookies and biscuits. After giving away 80% of the biscuits and 90% of the cookies, she was left with twice as many biscuits as cookies. Find the number of cookies Kimberly gave away.
| |
Biscuits |
Cookies |
| Before |
5x2 =
10 u
|
10 u |
| Change |
- 4x2 =
8 u |
- 9 u |
| After |
1x2 =
2 u |
1 u |
Comparing biscuits and
cookies in the end |
2x1 =
2 u |
1x1 =
1 u |
80% =
80100 =
4590% =
90100 =
910The number of biscuits in the end is the repeated identity. Make the number of biscuits in the end the same. LCM of 1 and 2 is 2.
Total number of pastries at first
= 10 u + 10 u
= 20 u
20 u = 441
1 u = 441 ÷ 20 = 12
Number of cookies that Kimberly gave away
= 9 u
= 9 x 12
= 108
Answer(s): 108
