Answer:
1/6 of a ton.
Step-by-step explanation:
In the morning, 2/15 of a ton is fed to the fishes.
In the afternoon, weight of the feed will be 1/15 of a ton more than the fish fed during the morning.
i.e. 2/15 +1/15 = 3/15
If the total weight of fish feed in a day is 1/2 of a ton.
Therefore:
Morning Feed + Afternoon Feed + Night Feed = ½
2/15 + 3/15 + Night Feed = ½
5/15 + Night Feed = ½
⅓ + Night Feed = ½
Night Feed = ½ - ⅓ = 1/6
Therefore, in the night, the fish are fed 1/6 of a ton.