After using
17 of her sugar, Mrs Goh bought another 30 kg of sugar. As a result, Mrs Goh now has
97 as much sugar as what she had at first. How many kilograms of sugar did Mrs Goh have at first?
| |
Sugar |
Total |
| Before |
7 u |
7 u |
| Change 1 |
- 1 u |
|
| After 1 |
6 u |
|
| Change 2 |
+ 30 |
|
| After 2 |
6 u + 30 |
9 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 30 kg of sugar = 6 u + 30
6 u + 30 = 9 u
9 u - 6 u = 30
3 u = 30
1 u = 30 ÷ 3 = 10
Amount of sugar that Mrs Goh had at first
= 7 u
= 7 x 10
= 70 kg
Answer(s): 70 kg
