After using
17 of her sugar, Mrs Yong bought another 12 kg of sugar. As a result, Mrs Yong now has
107 as much sugar as what she had at first. How many kilograms of sugar did Mrs Yong have at first?
| |
Sugar |
Total |
| Before |
7 u |
7 u |
| Change 1 |
- 1 u |
|
| After 1 |
6 u |
|
| Change 2 |
+ 12 |
|
| After 2 |
6 u + 12 |
10 u |
Fraction of sugar left after using
17 of it
= 1 -
17 =
67 Amount of sugar left after using some = 6 u
Amount of sugar after buying 12 kg of sugar = 6 u + 12
6 u + 12 = 10 u
10 u - 6 u = 12
4 u = 12
1 u = 12 ÷ 4 = 3
Amount of sugar that Mrs Yong had at first
= 7 u
= 7 x 3
= 21 kg
Answer(s): 21 kg
