What is X for this 4x/3-3x+1=10

The table shows the webster family’s monthly expenses for the first three months of the year. they are $2,687.44, $2,613.09, and $2,808.64. what is the average monthly expenditure for all expenses?

Adam used 1072.4 gallons of water over the course of 7 days. how much water did adam use, on average, each day?

I’m really confused and need your assist me with this question i’ve never been taught