SOLUTION: I need help with this problem. The inner rectangle whose length is 7 inches and width is 13 inches is surrounded by a rectanglar frame whose uniform thickness is 2.5 inches. Find t

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Question 277305: I need help with this problem. The inner rectangle whose length is 7 inches and width is 13 inches is surrounded by a rectanglar frame whose uniform thickness is 2.5 inches. Find the area.
Found 2 solutions by mananth, oberobic:
Answer by mananth(16949) About Me  (Show Source):
You can put this solution on YOUR website!
I need help with this problem. The inner rectangle whose length is 7 inches and width is 13 inches is surrounded by a rectanglar frame whose uniform thickness is 2.5 inches. Find the area.
length = 7 inches
width = 13 inches
rectangular frame width = 2.5 inches. This width is on both sides of the length and width
Add 5 to width and length


The length then becomes 7+5 = 12 inches
width becomes 13+5 = 18 inche.
The area including frame = 12 * 18 =216 sq. inches
Original area = 7*13= 91 square inches
the difference will give area of the frame

Answer by oberobic(2304) About Me  (Show Source):
You can put this solution on YOUR website!
Given the uniform width of the border is 2.5 inches, then you will need to add 5 inches to the inner rectangle's length and width to determine the outer rectangle's area:
l + 5 = 7 + 5 = 12
w + 5 = 13 + 5 = 18
So, the outer rectangle's area = l*w = 12*18 = 216
.
The inner rectangle's are = 7 * 13 = 91
.
That means the area of the 'border' = 216 - 91 = 125
.
Done