-4/5+7/12 simplify the expression

Apublic library wants to place 4 magazines and 9 books on each display shelf. the expressions 4s +9s represents the total number of items that will be displayed on s shelves. simplify this expression

Abag has more green balls than blue balls, and there is at least one blue ball. let bb represent the number of blue balls and let gg represent the number of green balls. let's compare the expressions 2b2b and b + gb+g. which statement is correct? choose 1

You have 3 boxes, one "strawberries"; one "mentos" and one "mixed".but you know that all the labels are in incorrect order .how do you know witch is witch?