How do you write an expression with words

Pick the description of a geometric object that best matches the real world object box for a deck of card

Which formula finds the probability that a point on the grid below will be in the blue area? p(blue) = total number of squares number of blue squares number of blue squares p(blue) = total number of squares number of blue squares p(blue) = number of white squares

Which simplifys to a+ b? a-(1-b)+1 -(1-a)-b+1 (a--1) -1)+1