Question

Find the perimeter of the figure. If you need to use pi in your computation, approximate its value as 3.14.

Rectangle topped by a semicircle

a.
98.10 m

b.
52.57 m

c.
89.55 m

d.
74.55 m

Answer 1

The correct option is C. 89.55 meter

Explanation:

The perimeter of the given figure can be calculated by dividing the figure into two parts : One is semi-circle and second is rectangle.

To find Perimeter of rectangle :

Length of the rectangle = 18 m

Width of the rectangle = 15 m

Perimeter = 2 × (Length + Width)

⇒ Perimeter = 2 × (18 + 15)

⇒ Perimeter = 2 × 33

⇒ Perimeter = 66 meters

To find perimeter of semi-circle :

Radius of semi-circle = 7.5 m

Perimeter of semi-circle = π × radius

⇒ Perimeter = 3.14 × 7.5

⇒ Perimeter = 23.55 meter

So, Total Perimeter of the figure = 66 + 23.55

= 89.55 meter

Therefore, The correct option is C. 89.55 meter

Answer 2

To solve this problem you must apply the proccedure shown below:
As you can see in the figure attached above, the figure has a semicircle and a rectangle, then, you have that the perimeter is:
P=(18x2)+15+(15/2)(3.14)
P=36+15+23.55
P=74.55
Therefore, as you can see, the answer for this exercise is the last option, the option d, which is: d. 74.55