The perimeter of a triangle is 20 cm and the inradius of the triangle is 3 cm. What is the area of the triangle?  Choose the correct choice from the following choices
A) 22
B) 30
C) 77
D) 54
E) 23
Area of a triangle = r * s   Where r is the inradius and s is the semi perimeter of the triangle.   Area of triangle = 3 * 20/2= 
<gadget id="calculator">3 * 20/2</gadget>
<output>30</output>
30 cm2   Answer:30
<result>B</result>
The perimeter of a triangle is 20 cm and the inradius of the triangle is 3 cm. What is the area of the triangle?