After using
37 of her rice flour, Mrs Chua bought another 30 kg of rice flour. As a result, Mrs Chua now has
107 as much rice flour as what she had at first. How many kilograms of rice flour did Mrs Chua have at first?
| |
Rice Flour |
Total |
| Before |
7 u |
7 u |
| Change 1 |
- 1 u |
|
| After 1 |
4 u |
|
| Change 2 |
+ 30 |
|
| After 2 |
4 u + 30 |
10 u |
Fraction of rice flour left after using
37 of it
= 1 -
37 =
47 Amount of rice flour left after using some = 4 u
Amount of rice flour after buying 30 kg of rice flour = 4 u + 30
4 u + 30 = 10 u
10 u - 4 u = 30
6 u = 30
1 u = 30 ÷ 6 = 5
Amount of rice flour that Mrs Chua had at first
= 7 u
= 7 x 5
= 35 kg
Answer(s): 35 kg
