Express the area A of a rectangle as a function of the width W if the length of the rectangle is twice its width.

Gabrielle's age is two times mikhail's age. the sum of their ages is 84. what is mikhail's age?

Kristen is wrapping presents for the holidays. she has a box that measures 4 ft. x 2 ft. x 2 ft. how many square feet of wrapping paper does she need to cover the box without overlapping?

Describe a situation where it would be beneficial to round decimals to the nearest dollar. explain why you would use rounding in that situation.