Luis had some pastries.
37 of them were puffs. The rest were tarts. He sold
25 of the puffs and 6 tarts. In the end, he had 139 pastries left. How many pastries did he sell?
| |
Puffs |
Tarts |
Comparing pastries
at first |
3x5 =
15 u |
4x5 =
20 u |
Before
|
5x3 =
15 u |
20 u |
Change
|
- 2x3 =
- 6 u |
- 6 |
After
|
3x3 =
9 u |
20 u - 6 |
The number of puffs at first is repeated. Make the number of puffs at first the same. LCM of 3 and 5 is 15.
Total number of pastries left
= 9 u + 20 u - 6
= 29 u - 6
29 u - 6 = 139
29 u = 139 + 6
29 u = 145
1 u = 145 ÷ 29 = 5
Number of pastries that Luis sold
= 6 u + 6
= 6 x 5 + 6
= 30 + 6
= 36
Answer(s): 36
