15. The diameter of a circle is given as 10 cm, correct to the nearest cm. Calculate:
a) the maximum possible circumference
b) the minimum possible area of the circle consistent with this data
10cm correct to nearest cm" means the diameter could be arbitrarily close to (but less than) 10.5 cm. So the maximum possible circumference is 10.5π cm.
"10cm correct to nearest cm" also means that the diameter could be arbitrarily close to (but greater than) 9.5 cm. So the minimum possible area is π(9.5)²/4 cm²
