Final answer:
The length of the arc subtended by an angle of 7(π)/4 radians on a circle of radius 20 cm is 70 cm.
Step-by-step explanation:
To find the length of the arc subtended by an angle of 7(π)/4 radians on a circle of radius 20 cm, we can use the formula for the circumference of a circle. The circumference of a circle is given by the formula C = 2πr, where r is the radius. In this case, the radius is 20 cm, so the circumference is 2π(20) = 40π cm. The angle of 7(π)/4 radians is a fraction of a full revolution, so we can find the length of the arc by multiplying the circumference by the fraction of the angle: 40π x (7(π)/4)/(2π) = 70 cm.