After using
211 of her flour, Mrs Lin bought another 18 kg of flour. As a result, Mrs Lin now has
1211 as much flour as what she had at first. How many kilograms of flour did Mrs Lin have at first?
| |
Flour |
Total |
| Before |
11 u |
11 u |
| Change 1 |
- 1 u |
|
| After 1 |
9 u |
|
| Change 2 |
+ 18 |
|
| After 2 |
9 u + 18 |
12 u |
Fraction of flour left after using
211 of it
= 1 -
211 =
911 Amount of flour left after using some = 9 u
Amount of flour after buying 18 kg of flour = 9 u + 18
9 u + 18 = 12 u
12 u - 9 u = 18
3 u = 18
1 u = 18 ÷ 3 = 6
Amount of flour that Mrs Lin had at first
= 11 u
= 11 x 6
= 66 kg
Answer(s): 66 kg
