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In a laboratory, the count of bacteria in a certain experiment was increasing at the rate of 2.5% per hour. Find the bacteria at the end of 2 hours if the count was initially 5,06,000.

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Question

In a laboratory, the count of bacteria in a certain experiment was increasing at the rate of 2.5% per hour. Find the bacteria at the end of 2 hours if the count was initially 5,06,000.

Sum
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Solution

Let the number of bacteria initially = P

And number of bacteria at the end of 2 hours = A

Given initial number of bacteria (P) = 5,06,000

Time (n) = 2 years

Rate (R) = 2.5% p.a.

Number of bacteria at the end of 2 hours

(A) = P `(1+"R"/100)^"n"`

= 5,06,000 `(1+2.5/100)^2`

= 5,06,000 `(1+1/40)^2`

= 5,06,000 `(41/40)^2`

= 5,31,616.25

Hence, number of bacteria at the end of 2 hours (A) = 5,31,616.25

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Chapter 7: Comparing Quantities - EXERCISE 7.3 [Page 90]

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NCERT Mathematics [English] Class 8
Chapter 7 Comparing Quantities
EXERCISE 7.3 | Q 2. | Page 90

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