After using
15 of her sugar, Mrs Sih bought another 15 kg of sugar. As a result, Mrs Sih now has
95 as much sugar as what she had at first. How many kilograms of sugar did Mrs Sih have at first?
| |
Sugar |
Total |
| Before |
5 u |
5 u |
| Change 1 |
- 1 u |
|
| After 1 |
4 u |
|
| Change 2 |
+ 15 |
|
| After 2 |
4 u + 15 |
9 u |
Fraction of sugar left after using
15 of it
= 1 -
15 =
45 Amount of sugar left after using some = 4 u
Amount of sugar after buying 15 kg of sugar = 4 u + 15
4 u + 15 = 9 u
9 u - 4 u = 15
5 u = 15
1 u = 15 ÷ 5 = 3
Amount of sugar that Mrs Sih had at first
= 5 u
= 5 x 3
= 15 kg
Answer(s): 15 kg
