Question

At the rate of $2.00 per square foot, the cost of painting the rectangular board with a semicircular top shown in the figure is $? Assuming pi = 3.14

I 've been stuck on this for so long can someone please help me out?!

Answer 1

3x4 =12 (this is the square)
1.5 x 1.5 x 3.14= 7.065 however since it is a half of circle we divide 7.065 by 2 = 3.5325
Now add 3.5325 and 12 = 15.5325 round it to 15.53 then multiply by $2
The answer is $31.06

Answer 2

The cost of painting the board is $31.06

To calculate the total cost we need to find the area is the figure( board)

The figure consist of a rectangle and a semi circle

area of a rectangle = l × w

where l is the length and w is the width

area = 4 × 3 = 12 ft²

Area of semi circle = 1/2πr²

= 1/2 × 3.14 × (3/2)²

= 3.53ft²

Total area = 12 + 3.53= 15.53 ft²

1 ft² will cost $2.00

15.53ft² will cost;

2 × 15.53

= $31.06

Therefore, the cost of painting the board is $31.06