Your dog has 7 fleas. The number triples every week. How many fleas after 2 weeks and 1 month?

Question

Ok so these are separate answers I just put it in one problem and how would you set this equation up

Answer 1

Hello Holland,

 

This is very similar to the nickel question you asked earlier, and I fully solved that one for you. This time I'm just explaining what you should do to solve the problem on your own.

 

First write an exponential equation to model the situation. In general y=a(b)^x where a is the initial value, b is the multiplier, and x is time. In this case your dog starts with 7 fleas so a = 7 and triple means to multiply by 3 so b = 3. You can use the values of a and b to write the equation.

 

To find out how many fleas your dog has after 2 weeks you want to find y when x = 2. Simply replace the x in your equation with 2 and simplify.

 

On average there are 4 and 1⁄3 weeks in a month, I would use that number for x. (I found this by dividing the number of weeks in a year by the number of months in a year). In this case you would replace the x in your equation with 4 and 1⁄3 and simplify.