Aunt Mary made 90 less wafers than puffs. After she gave 0.7 of the wafers and
25 of the puffs to Risa, she was left with 75 less wafers than puffs. How many puffs did she make?
| |
Wafers |
Puffs |
Comparing wafers
and puffs at first |
|
90 more |
Before |
10 u |
5x2 + 90 =
10 u + 90 |
Change |
- 7 u |
- 2x2 - 36 =
- 4 u - 36
|
After |
3 u |
3x2 + 54 =
6 u + 54 |
Comparing wafers
and puffs in the end |
|
75 more |
0.7 =
710 25 x 90 = 36
Number of puffs that Aunt Mary gave to Risa = 4 u + 36
If Aunt Mary made another 75 wafers in the end, the number of wafers and puffs in the end would be the same.
6 u + 54 = 3 u + 75
6 u - 3 u = 75 - 54
3 u = 21
1 u = 21 ÷ 3 = 7
Number of puffs that Aunt Mary made
= 10 u + 90
= 10 x 7 + 90
= 70 + 90
= 160
Answer(s): 160
