tentukan s4 dari bilangan geometri 48,12,3 bila a: 48 & r:1\4

S4 = a(1 - r⁴) / (1 - r)
S4 = 48(1 - (¼)⁴) / (1 - ¼)
= 48(1 - (1/256)) / (3/4)
= 48(255/256) / (3/4)
= 48(255/256) × (4/3)
= 48(255/64)×(1/3)
= 16(255/64)
= 255/4
= 63(3/4)