Let's assume that bacteria doubles every 10 minutes. if a culture begins with exactly
30 bacterial cells, how many bacteria will be present after 1 hour?

a 960 bacteria
b 1000 bacteria
c 1520 bacteria
d 1920 bacteria

Greetings!

First off, we should know that there are 60 minutes in an hour. Therefore, the first step we will need to do, is divide 60 by 10.

60 ÷ 10 = 6

As shown above, we now know we will have to double the number 6 times. If we start with 30, this will be our first problem.

(1)   30 + 30 = 60

And so on and so forth...

(2)   60 + 60 = 120

(3)   120 + 120 = 240

(4)   240 + 240 = 480

(5)   480 + 480 = 960

(6)   960 + 960 = 1920

And after our sixth time we have our

1920 bacteria

Hope this helps!

~Fluerie

the solution of the equation is 2.23 ⇒ answer b

step-by-step explanation:

* lets revise the meaning of exponential function

- the form of the exponential function is y = ab^x, where a ≠ 0, b > 0 ,  

  b ≠ 1, and x is any real number

- it has a constant base b

- it has a variable exponent x

- to solve an exponential equation, take the log or ln of both sides,  

  and solve for the variable

* lets solve the problem

∵

- the base is 7 and the exponent is x

- insert ㏑ in both sides

∴

- use the rule

∴ x ㏑(7) = ㏑(77)

- to find x divide both sides by ㏑(7)

∴

* the solution of the equation is 2.23 to the nearest 2 decimal places