Answer :

Given: there were 30 bacteria present originally and culture doubles every hour.

∴ a_{0} = 30

∴ After an hour culture is a_{0} × 2 = 30 × 2 = 60

Since the count doubles every hour it forms a G.P. with r = 2

Let the G.P be a_{0},a_{1}r,a_{2}r^{2}........

⇒ The culture at the end of 2^{nd} hour = ar^{2} = 30 × 2^{2} = 120

⇒ The culture at the end of 4^{th} hour = ar^{4} = 30 × 2^{4} = 480

⇒ The culture at the end of n^{th} hour = ar^{n} = 30 × 2^{n}

∴ Culture at end pf 2^{nd} , 4^{th} , n^{th} hours are 120, 480, 30 × 2^{n} respectively.

Rate this question :

The product of thRD Sharma - Mathematics

Express <imRS Aggarwal - Mathematics

If a, b, c are inRS Aggarwal - Mathematics

Express <imRS Aggarwal - Mathematics

Prove that RS Aggarwal - Mathematics

If a, b, c are inRS Aggarwal - Mathematics

The sum of n termRS Aggarwal - Mathematics

If a, b, c, d areRS Aggarwal - Mathematics

Evaluate :

</pRS Aggarwal - Mathematics

The first term ofRS Aggarwal - Mathematics