Question

Suatu tabung mempunyai luas permukaan 253 cm² . jika keliling alas tabung tersebut 22 cm , maka volume tabung adalah

Answer 1

K alas tabung = 22
2.phi.r = 22
2.22/7.r = 22
44/7.r = 22
44.r = 22.7
44.r = 154
r = 154/44
r = 3,5 cm


maka :


Lp tabung = 253
2.phi.r.(r+t) = 253
2.22/7.3,5.(3,5+t) = 253
44/2.(3,5+t) = 253
22.(3,5+t) = 253
77+22.t = 253
22.t = 253-77
22.t = 176
t = 176/22
t = 8 cm

jadi,
V tabung
= phi.r².t
= 22/7.(3,5)².8
= 22/7.12,25.8
= 308 cm kubik