Lucy made 135 shortbreads and scones. After she gave 0.3 of the shortbreads and 0.8 of the scones to her children, she was left with an equal number of shortbreads and scones. How many shortbreads had she left?
| |
Shortbreads |
Scones |
Before
|
10x1 =
10 u |
5x7 =
35 u |
Change
|
- 3x1 =
- 3 u |
- 4x7 =
- 28 u |
After
|
7x1 =
7 u |
1x7 =
7 u |
Comparing shortbreads and
scones in the end |
1x7 =
7 u |
1x7 =
7 u |
0.3 =
310 0.8 =
810 =
45 The number of shortbreads and scones is the same in the end. Make the number of shortbreads and scones in the end the same. LCM of 7 and 1 and 1 is 7.
Total number of shortbreads and scones at first
= 10 u + 35 u
= 45 u
45 u = 135
1 u = 135 ÷ 45 = 3
Number of shortbreads that Lucy had left
= 7 u
= 7 x 3
= 21
Answer(s): 21
