Find the area of a circle if 3/8 of the circumference of this circle is 60 cm.

1. Determine the circumference of the circle. We take it for a and make up the proportion:

3/8 – 60 cm, 1 – a cm;

3/8: 1 = 60: a;

a = (1 x 60): 3/8;

a = 60 x 8/3;

a = (60 x 8): 3;

a = 160 cm;

2. Determine the radius of the circle:

d = 160: 2: 22/7 = 80: 22/7 = 80 x 7/22 = (80 x 7): 22 = 560/22 cm;

3. Determine the area of the circle:

22/7 x (560/22) ² = (22/7 x 560/22) x 560/22 = 80 x 560/22 = 2036.4 / 11 cm².

Answer: the area of the circle is 2036.4 / 11 cm²