Question

Rahul's dad was seeing the plan of their new house, the outline of the house is shown in the figure.

Rahul's Dad asked him to find the value of "x” if the perimeter of the outline is 101 cm.
What is the value of x?

• A. 9
• B. 10
• C. 11
• D. 12

Answer 1

The correct option is B

10

Perimeter of the outline is the sum of the length of all the sides.
Perimeter = (x+2) + (2x+1) + (2x+10) + (x+2) + (x+3) + (x+3)
Group the variable and numbers,
(x + 2x + 2x + x + x + x) + (2 + 1 + 10 + 2 + 3 + 3) = (8x) + (21)
Given that, perimeter is equal to 101 cm
So, 8x + 21 = 101
Subtract 21 from both sides give,
8x + 21 - 21 = 101 - 21
8x = 80
Divide both sides by 8,
$\frac{8x}{8}$ = $\frac{80}{8}$

x = 10.