Two circles touch internally and their centres are O and O’ as shown. The sum of their areas is 180𝜋 sq cm and the distance between their centres is 6 cm. Find the diameter (in cm) of the larger circle.

 Two circles touch internally and their centres are O and O’ as shown. The sum of their areas is 180𝜋 sq cm and the distance between their centres is 6 cm. Find the diameter (in cm) of the larger circle.

 

	A	16
	B	12
	C	18
	D	24

Solution : D