PSLEIrene made some sandwiches to sell.
34 of them were egg sandwiches and the rest were mushroom sandwiches. After selling 210 mushroom sandwiches and
56 of the egg sandwiches, she had
15 of the sandwiches left. How many sandwiches did Irene sell?
|
Egg sandwiches |
Mushroom sandwiches |
Total |
Comparing egg sandwiches and mushroom sandwiches at first |
3x2 |
1x2 |
4x2
|
Before |
6x1 |
|
|
Change |
- 5x1
|
- 210 |
|
After |
1x1
|
|
|
|
Egg sandwiches |
Mushroom sandwiches |
Total |
Before |
6 u |
2 u |
8 u
|
Change |
- 5 u
|
- 210 |
|
After
|
1 u
|
2 u - 210
|
15 x 8 u = 135 u |
The number of egg sandwiches at first is repeated. Make the number of egg sandwiches at first the same. LCM of 3 and 6 is 6.
Number of sandwiches left
= 1 u + 2 u - 210
= 3 u - 210
3 u - 210 = 1
35 u
3 u - 1
35 u = 210
1
25 u = 210
1 u = 210 ÷ 1
25 = 150
Total number of sandwiches that Irene sold
= 5 u + 210
= 5 x 150 + 210
= 750 + 210
= 960
Answer(s): 960