Zara baked a total of 323 cookies and puffs. After giving away 90% of the puffs and 75% of the cookies, she was left with twice as many puffs as cookies. Find the number of cookies Zara gave away.
| |
Puffs |
Cookies |
| Before |
10x2 =
20 u
|
4 u |
| Change |
- 9x2 =
18 u |
- 3 u |
| After |
1x2 =
2 u |
1 u |
Comparing puffs and
cookies in the end |
2x1 =
2 u |
1x1 =
1 u |
90% =
90100 =
91075% =
75100 =
34The number of puffs in the end is the repeated identity. Make the number of puffs in the end the same. LCM of 1 and 2 is 2.
Total number of pastries at first
= 20 u + 4 u
= 24 u
24 u = 323
1 u = 323 ÷ 24 = 12
Number of cookies that Zara gave away
= 3 u
= 3 x 12
= 36
Answer(s): 36
