Given that there were 30 bacteria present originally. a=30 Also given that the number doubles every one hour. After one hour the count =2×30=60 Since the count doubles every hour it forms a G.P. with r=2 a,ar,ar2........ The count at the end of 2nd hour=ar^2=30×2^2=120 The count at the end of 4th hour=ar^4=30×2^4=480 The count at the end of 8th hour=ar^8n=30×2^8=7680 etc. The count at the end of n^th hour=ar^n=30×2^n
Also, the equation y=30*(2)^8/1 give the same result y= 7680
