So basically you want to find the cost per day. So you have 5 days, so divide £100 by 5. You get £20 per day Now, the cost per child. We have 80 children so it would be £20/80 children per day. Our answer is £0.25 per child per day.
To solve this problem you can just do two separate division steps. You can divide £100 / 80 to find how much it costs to feed 1 child in a 5 day period £100 / 80 = £1.25/child per 5 days Then you can divide £1.25/5 to find how much it costs to feed 1 child in 1 day £1.25/5 = £.25