Dylan had some pastries.
38 of them were biscuits. The rest were cookies. He sold
34 of the biscuits and 6 cookies. In the end, he had 86 pastries left. How many pastries did he sell?
| |
Biscuits |
Cookies |
Comparing pastries
at first |
3x4 =
12 u |
5x4 =
20 u |
Before
|
4x3 =
12 u |
20 u |
Change
|
- 3x3 =
- 9 u |
- 6 |
After
|
1x3 =
3 u |
20 u - 6 |
The number of biscuits at first is repeated. Make the number of biscuits at first the same. LCM of 3 and 4 is 12.
Total number of pastries left
= 3 u + 20 u - 6
= 23 u - 6
23 u - 6 = 86
23 u = 86 + 6
23 u = 92
1 u = 92 ÷ 23 = 4
Number of pastries that Dylan sold
= 9 u + 6
= 9 x 4 + 6
= 36 + 6
= 42
Answer(s): 42
