The count of bacteria in a certain experiment was 40000. If the growth by 20persent in first hour,decreases by 20persent in second hours and again increase by 20pesent in the third hour, find the number of bacteria at the end of third hour.
Answers
Answer:
The number of bacteria at the end of third hour is 46080 nos
Step-by-step explanation:
Given : Initial Count of bacteria = 40000
first hour = 20% growth
second hour = 20% decrease
Third hour = 20% increase
no of bacteria at end of the third hour = ?
Solution : At the end of first hour = initial count + % growth
= 40000 +20% of 40000
= 40000 + 20/100 x 40000
= 40000 + 8000
= 48000 nos
At the end of second hour = first hour end count - %decrease
= 48000 - 20% of 48000
= 48000 - 20/100 x 48000
= 48000 - 9600
= 38400 nos
At the end of third hour = second hr end count + % growth
= 38400 + 20% of 38400
= 38400 + 7680
= 46080 nos