Lucy had 80 blueberry and cherry cookies. After giving away
15 of her blueberry cookies and 17 of her cherry cookies, she had an equal number of blueberry and cherry cookies. How many cherry cookies did she have at first?
| |
Blueberry cookies |
Cherry cookies |
Total |
| Before |
5 u |
4 u + 17 |
80 |
| Change |
- 1 u |
- 17 |
|
| After |
4 u |
4 u |
|
Fraction of the blueberry cookies left
= 1 -
15=
45 The number of blueberry and cherry cookies in the end is the same.
Total number of cookies at first
= 5 u + 4 u + 17
= 9 u + 17
9 u + 17 = 80
9 u = 80 - 17
9 u = 63
1 u = 63 ÷ 9 = 7
Number of cherry cookies at first
= 4 u + 17
= 4 x 7 + 17
= 28 + 17
= 45
Answer(s): 45
