A barrel contained 2.5 ℓ more water than a bottle. After some water was poured from the barrel to the bottle, both the barrel and the bottle had 5 ℓ of water each. How much water was there in the bottle at first?
| |
Barrel |
Bottle |
Total |
| Before |
1 u + 2.5 |
1 u |
10 |
| Change |
- ? |
+ ? |
|
| After |
5 |
5 |
10 |
Volume of water in the bottle = 1 u
Volume of water in the barrel = 1 u + 2.5
Total volume of water
= 1 u + 1 u + 2.5
= 2 u + 2.5
Total volume of water
= 2 x 5
= 10 ℓ
When water is poured from the barrel to the bottle, the total volume remains unchanged.
2 u + 2.5 = 10
2 u = 10 - 2.5
2 u = 7.5
1 u = 7.5 ÷ 2 = 3.75
Volume of water in the bottle at first = 3.75 ℓ
Answer(s): 3.75 ℓ
