An empty container has a capacity of 60000 litres to 1 significant figure Tony pours in 5400 litres of water to 1 significant figure He says "I have filled more than 10% of the container" Is he correct

The container's capacity could be anything from 55,000 to 65,000. Exactly 10% of that is anything from 5500 to 6500.

The amount of water poured in could be anything from 5350 or 5450. That is NOT in the range above, so the answer is NO.