After using
35 of her sugar, Mrs Zhang bought another 18 kg of sugar. As a result, Mrs Zhang now has
85 as much sugar as what she had at first. How many kilograms of sugar did Mrs Zhang have at first?
|
Sugar |
Total |
Before |
5 u |
5 u |
Change 1 |
- 1 u |
|
After 1 |
2 u |
|
Change 2 |
+ 18 |
|
After 2 |
2 u + 18 |
8 u |
Fraction of sugar left after using
35 of it
= 1 -
35 =
25 Amount of sugar left after using some = 2 u
Amount of sugar after buying 18 kg of sugar = 2 u + 18
2 u + 18 = 8 u
8 u - 2 u = 18
6 u = 18
1 u = 18 ÷ 6 = 3
Amount of sugar that Mrs Zhang had at first
= 5 u
= 5 x 3
= 15 kg
Answer(s): 15 kg