Question -
Answer -
Given, the number ofbacteria doubles every hour. Hence, the number of bacteria after every hourwill form a G.P.
Here we have, a =30 and r = 2
So, a3 = ar2 =(30) (2)2 = 120
Thus, the number ofbacteria at the end of 2nd hour will be 120.
And, a5 = ar4 =(30) (2)4 = 480
The number of bacteriaat the end of 4th hour will be 480.
an +1 = arn = (30) 2n
Therefore, the numberof bacteria at the end of nth hour will be 30(2)n.