Mrs. Martin wants to place a ribbon around the outer edge of a rectangular mirror. The area of the mirror is 324 square inches. The width of the mirror is 12 inches. How many inches of ribbon does Mrs. Martin need?
78, because 324 divided by 12 is 27. this means that the width is 12 and the length is 27. 27 times 2 equals 54 and 12 times 2 equals 24. 54+24= 78
Answer:
78 inches of ribbon does Mrs. Martin need
Step-by-step explanation:
Area of a rectangle (A) is given by:
\(A = lw\) .....[1]
where,
l is the length of the rectangle and w is the width of the rectangle.
As per the statement:
The area of the mirror is 324 square inches. The width of the mirror is 12 inches.
⇒A = 324 square inches and w = 12 inches.
By [1] we have;
\(324 = 12l\)
Divide both sides by 12 we have;
27 = l
or
l = 27 inches
We have to find the inches of ribbon does Mrs. Martin need.
Perimeter of the rectangle(P) = 2(l+w)
Substitute the given values we have;
\(P = 2 \cdot (27+12) = 2 \cdot 39 = 78 in\)
Therefore, 78 inches of ribbon does Mrs. Martin need