Three circles, each of radius 20 and centres at P, Q, R. Further, AB= 5, CD= 10 and EF= 12. What is the perimeter of the triangle PQR?
93
PR=PB+AR-5=20+20-5 [because AB =5 cm]
So, perimeter = PR +PQ+QR
=(20+20-5)+(20+20-10)+(20+20-12)
= 35+30+28=93