The number of bacteria in a certain culture doubles every hour. If there were 50 bacteria present in the culture originally, how many bacteria would be present at the end of (i) 2nd hour, (ii) 5th hour and (iii) nth hour?

To find: The number of bacteria after


(i) 2nd hour


(ii) 5th hour


(iii) nth hour


Given: (i) Initially, there were 50 bacteria


(ii) Rate – 100% per hour


The formula used:


(i) For 2nd hour







(ii) For 5th hour







(iii) For nth hour






Ans) Number of bacteria in a 2nd hour will be 200, the number of bacteria in a 5th hour will be 1600 and number of bacteria in an nth hour will be


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