To find the measure of angle PQR, we can use the relationship between an inscribed angle and the arc it intercepts. The measure of an inscribed angle is always half the measure of the arc that it intercepts.
In this case, angle PQR intercepts arc QR. Therefore, we can calculate the measure of angle PQR as follows:
Measure of angle PQR = 1/2 × Measure of arc QR
Substituting the given value:
Measure of angle PQR = 1/2 × 100 = 50 degrees
Thus, the measure of angle PQR is 50 degrees.