Hello, Peacewanters007!
I couldn't find an Arithmetic solution.
I had to use Algebra . . . sorry.
A jug weighed 1.8 kg when 2/7 of it was filled with water
and weighed 2.85 kg when it was filled 5/7.
Find:
(a) Weight of jug when it was empty.
(b) What was mass of jug when it was completely filled?
Let = weight of the empty jug.
Let = weight of water when jug is completely filled.
Code:
* *
| |
| |
| |
| - - - | 1.8 kg
|:::::::|
| 2/7 W |
|:::::::|
*-------*
J
When the jug is full, the total weight is 1.8 kg.
Equation #1: .
Code:
* *
| |
| - - - |
|:::::::|
|:::::::| 2.85 kg
| 5/7 W |
|:::::::|
|:::::::|
*-------*
J
When the jug is full, the total weight is 2.95 kg.
Equation #2: .
Subtract [1] from [2]: . .
Hence: .
Substitute into [1]: .
(a) The empty jug weighed: .
(b) The filled jug weighed: .