Bacteria in a pond multiplies as shown in the table. if a fungus on a tree decays at half that rate, what is the rate of decay (round to the nearest integer)?
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20%

Step-by-step explanation:

Population growth formula:

where P is the total population after time t,    is the starting population, r is the rate of growth and t is the time in hours

Solving for r:

and replacing with data:

P =  22.781

= 4.5 (taking hour 2 as initial time)

t = 4 hours (time elapsed between initial time and time the population reach P)

r = 0.4, that is equivalent to 40%

Then, fungus decay rate is 40%/2 = 20%

n=9

step-by-step explanation:

7 times a number = 7n

decreased by 13 = 7n-13

same as is =

5 times the number = 5n

increased by 5 = 5n+5

7n-13 = 5n+5

2n=18

n=9