A baker regularly uses flour to make pastries for the bakery at the beginning of the month of the Baker has a 25 pound bag of flour. Each week she uses 5 3/5 pounds of flour write an expression to represent the change in weight of the bag of flour over four weeks

At the beginning, she has 25lb of flour.

Each week, she ses (5 + 3/5) pounds of flour.

Then after the first week, she has a total of:

W(1) = 25lb - (5 + 3/5)lb

After another week, she has:

W(2) = 25lb - (5 + 3/5)lb - (5 + 3/5)lb = 25lb - 2*(5 + 3/5)lb

and so on.

if x represents the number of weeks, the equation is:

W(x) = 25lb - x*(5 + 3/5)lb

where x can be {0, 1, 2, 3, 4}

That is the equation that represents the change in the weight for the first four weeks.

a_n = a_1 + (n - 1)d

the first term is 6.

the common difference d = ?

when you find d, replace n with 7 and d with the common difference to find your answer.