The number of bacteria in a culture doubles every hour. If there were

1.	The number of bacteria in a culture doubles every hour. If there were 50 bacteria originally in the culture, how many bacteria will be there at the end of the 5th hour?
Answer» Since the number of bacteria in culture doubles every hour, increase in number of bacteria after every hour is in G.P. \(\therefore\) a = 50, r = 100/50 = 2 t_n = ar^n-1 To find the number of bacteria at the end of the 5th hour. (i.e., to find the number of bacteria at the beginning of the 6th hour, i.e., to find t₆.) \(\therefore\) t₆ = ar⁵ = 50 x (2⁵) = 50 x 32 = 1600

The number of bacteria in a culture doubles every hour. If there were 50 bacteria originally in the culture, how many bacteria will be there at the end of the 5th hour?

Answer»

Since the number of bacteria in culture doubles every hour, increase in number of bacteria after every hour is in G.P.

\(\therefore\) a = 50, r = 100/50 = 2

t_n = ar^n-1

To find the number of bacteria at the end of the 5th hour.

(i.e., to find the number of bacteria at the beginning of the 6th hour, i.e., to find t₆.)

\(\therefore\) t₆ = ar⁵

= 50 x (2⁵)

= 50 x 32

= 1600