Hello, and sorry for my English, as I am Norwegian.

I have a statics problem which I can not understand.

I've taken a pic from my book:

The problem asks me to find the largest bending stress, σ

_{b}, in the incisions 1 and 2.

I have the solution in front of me, I just don't understand what they have done with the evenly distributed force (q). Especially in incision 2, when they find M

_{b}, they have used: M

_{b} = F

_{A}*a

_{A}-q*2.5m*1.25.

The q*2.5m I can understand, but where does the 1.25 come from? I thought it should be divided by 2?

Can someone explain how this works for me?