volume sebuah tabung diketahui 13.860 cm3, dan tingginya 40 cm. diameter tabung tersebut adalah...... a. 21 cm b. 18 cm c. 15 cm d. 11cm

V = 22/7 x r^2 x 40
13.860 = 880/7 x r^2
110,25 = r^2
r = 10,5 cm
diameter = 2 x 10,5 = 21 cm (A)

Vtabung = 13.860
πr²t   = 13.860
3,14xr²x40 = 13.860
125,6 r² = 13.860
r² = 13.860/125,6
r²=110
r =√110
r = 10,5
diameter = 10,5x2 = 21 cm
jadi jawabannya ( a = 21 cm)