How are developmental milestones useful for making decisions about early childhood education?

Negative 5 1/12 + negative 4 1/4 + 6 3/4

The perimeter of a rectangle is 42 inches. if the width of the rectangle is 6 inches, what is the length

Sophia wrote an equation to represent the revenue of a movie theater for one day. she let x represent the number of child tickets sold and y represents the nunver of adult tickets sold. if a child ticket cost $4, an adult ticket cost $6, and the total revenue for the daybwas $420, which equation could sophia use to represent the number of chikd and adult tickets that were sold?