Question

Marco is studying a type of mold that grows at a fast rate.he created the function f(x)=345(1.30)^x to model the number of mold spores per week. What does the 1.30 represent? How many mold spores are there after 4 weeks? Round your answer to the nearest whole number.

Answer 1

Answer:-  (1) 1.30 represents the rate of growth of mold spores per week.

(2)There are 985 mold spores in 4 weeks .

Explanation:-

The exponential function is given by $f(x)=C(1+r)^x$ , where C is the initial amount , r is the rate of growth and x is time period.

The given function is $f(x)=345(1.30)^x$ , where  initial number of mold spores= 345 and x is the time in weeks.

Now, $f(x)=345(1.30)^x=345(1+.30)^x$

Here we can see that r = 0.30 =30%

Therefore ,1.30 represents the rate of growth of mold spores per week.

Now, mold spores after 4 weeks  i.e. at  x=4

$f(4)=345(1.30)^4=345(2.85)=985.35\approx985$

There are 985 mold spores in 4 weeks.

Answer 2

I did the test, and the answer was D.) 1.30 represents the 30% rate of weekly growth; 985.