Diketahui luas selimut tabung 506 cm². Jika tingginya 16cm,hitung panjang jari jari alas tabung.

Dik. Luas selimut tabung (Lst) = 506 cm^2, tinggi = 16cm.
Dit. Panjang jari jari (r) ?

Jawab...

Luas selimut tabung (Lst) = 2 × phi × r × t
@ Lst = 2 × phi × r × t
@ 506 = 2 × 22/7 × r × 16
@ 506 = 32 × 22/7 × r
@ 506 × 7/22 = 32 × r
@ 161 = 32 × r
@ r = 161/32
@ r = 5,03 cm

Semoga membantu.. ^_^