Help please!

The number of visitors to certain web site triples every month.
The number of visitors is modeled by the expressions 8100 * 3^m , where m is the number of months after the number of visitors was measured. Evaluate the expression m = -4. What does the value of the expression represent in the situation .

Question

Help please!

The number of visitors to certain web site triples every month. 
The number of visitors is modeled by the expressions 8100 * 3^m , where m is the number of months after the number of visitors was measured. Evaluate the expression m = -4. What does the value of the expression represent in the situation .

campbell_st · Answer

well m = -4 

you have to remember negative powers indicate fractions 

$$x^{-a} = \frac{1}{x^a}$$

apply that index law here and you get

$$8100 \times 3^{-4} = \frac{8100}{3^4}$$

all you need to do is evaluate

hope it helps

anonymous · Answer

I evaluate 8100/3^4 .. ?  @campbell_st

campbell_st · Answer

well what is 

$$3^4 = 3 \times 3 \times 3 \times 3 = ?$$