If the number of bacteria increases twice every 20 minutes, how will it increases within two hours ?

64

Step-by-step explanation:

ASSUMING WE STARTED WITH ONE BACTERIA

there are 3 20 minute marks in an hour.

3 x 2 =  6

So are going to do the following

1 x 2 = 2

2 x 2 = 4

4 x 2 = 8

8 x 2 = 16

16 x 2 = 32

32 x 2 = 64

...

So in two hours a bacteria that increases two times every twenty minutes would multiply into sixtyfour bacteria in 2 hours.

the probability is 0