saya minta bantuan nya kak...

U1 = a = 5
U2 = ar = 10
r = 10/a = 10/5 = 2

Un = a × r^n
320 = 5 × 2^n
2^n = 320/5
2^n = 64
2^n = 2^6
n = 6

jml bakteri mjd 320 setelah 6 detik