English

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. - Mathematics

Advertisements
Advertisements

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
Advertisements

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

shaalaa.com
  Is there an error in this question or solution?
Chapter 8: Comparing Quantities - Exercise 8.3 [Page 134]

APPEARS IN

NCERT Mathematics [English] Class 8
Chapter 8 Comparing Quantities
Exercise 8.3 | Q 11 | Page 134

Video TutorialsVIEW ALL [1]

RELATED QUESTIONS

A scooter was bought at Rs 42,000. Its value depreciated at the rate of 8% per annum. Find its value after one year.


Compute the amount and the compound interest in  the following by using the formulae when:
Principal = Rs 160000, Rate = 10 paise per rupee per annum compounded half-yearly, Time = 2 years.


In how much time will a sum of Rs 1600 amount to Rs 1852.20 at 5% per annum compound interest?


The annual rate of growth in population of a certain city is 8%. If its present population is 196830, what it was 3 years ago?


6400 workers were employed to construct a river bridge in four years. At the end of the first year, 25% workers were retrenched. At the end of the second year, 25% of those working at that time were retrenched. However, to complete the project in time, the number of workers was increased by 25% at the end of the third year. How many workers were working during the fourth year?


Jitendra set up a factory by investing Rs 2500000. During the first two successive years his profits were 5% and 10% respectively. If each year the profit was on previous year's capital, compute his total profit.


Ms. Cherian purchased a boat for Rs 16000. If the total cost of the boat is depreciating at the rate of 5% per annum, calculate its value after 2 years.


On the construction work of a flyover bridge there were 320 workers initially. The number of workers were increased by 25% every year. Find the number of workers after 2 years.


A principal amounts to ₹ 13,924 in 2 years by compound interest at 18 p.c.p.a. Find the principal.


The population of a town was decreasing every year due to migration, poverty and unemployment. The present population of the town is 6,31,680. Last year the migration was 4% and the year before last, it was 6%. What was the population two years ago?


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×