Arectangle has a a width of 9 inches the area is 648 inches what is the length of the rectangle

The formula for a rectangle is length*width=area. Since we know the area and the width, we plug it in to the formula, we get length*9=648. 
l*9=648 is equivalent to l=648/9. Now we solve l=648/9 and get l=72. SO the width is 72 inches. 

When rates are expressed as a quantity of 1, such as 2 feet per second or 5 miles per hour, they are called unit rates. if you have a multiple-unit rate such as 120 students for every 3 buses, and want to find the single-unit rate, write a ratio equal to the multiple-unit rate with 1 as the second term.