After using
29 of her bread flour, Mrs Hun bought another 21 kg of bread flour. As a result, Mrs Hun now has
109 as much bread flour as what she had at first. How many kilograms of bread flour did Mrs Hun have at first?
| |
Bread Flour |
Total |
| Before |
9 u |
9 u |
| Change 1 |
- 1 u |
|
| After 1 |
7 u |
|
| Change 2 |
+ 21 |
|
| After 2 |
7 u + 21 |
10 u |
Fraction of bread flour left after using
29 of it
= 1 -
29 =
79 Amount of bread flour left after using some = 7 u
Amount of bread flour after buying 21 kg of bread flour = 7 u + 21
7 u + 21 = 10 u
10 u - 7 u = 21
3 u = 21
1 u = 21 ÷ 3 = 7
Amount of bread flour that Mrs Hun had at first
= 9 u
= 9 x 7
= 63 kg
Answer(s): 63 kg
