Ratio of CSA & TSA of cylinder is 1:2, find volume If T.S.A 616 cm2.
As we know that,TSA of cylinder =2πrh+2πr2
CSA of cylinder =2πrh
Volume of cylinder =πr2h
Now,
CSATSA=12(Given)
∵TSA=616cm2(Given)
∴CSA=12×616
⇒CSA=308cm2
Now,
TSA=CSA+2πr2
616−308=2πr2
⇒r2=308×722×2=49cm2
⇒r=7cm
Also,
2πrh=2πr2=308cm2
⇒2πrh=2πr2
⇒r=h
Therefore,
Volume of cylinder =πr2h
=227r3(∵r=h)
=227×(7)3=1078cm3