Lenox ironed 1/4 of the shirts over the weekend. she plans to split the remainder of the work equally over the next 5 evenings. what fraction of the shirts will she need to iron each day after school? b. if she has 40 shirts, how many shirts will she need to iron on thursday and friday?

Let the number of the shirts of Lexon be A.

She ironed 1/4 or A over the weekend, so 3/4 of A are left  to iron during the 5 weekdays.

So Lenox, each week day will iron:

 

that is 3/20 of A, the total number of his shirts.

If she has 40 shirts, that is if A=40, on Thursday and Friday, she will iron: 

shirts.

3/20  of the shirts ;   12 shirts