A culture of a certain bacteria doubles every hour. At 9:00 a.m, there were already 120 bacteria. Which equation represents the number of bacteria, n , at 8:00 a.m? How many bacteria were there?(1 point)

Responses

2n=120; at 8:00 a.m., there were 240 bacteria.
2 n equals 120 ; at 8:00 a.m., there were 240 bacteria.

2n=120; at 8:00 a.m., there were 60 bacteria.
2 n equals 120 ; at 8:00 a.m., there were 60 bacteria.

n2=120; at 8:00 a.m., there were 240 bacteria.
Start Fraction n over 2 End Fraction equals 120 ; at 8:00 a.m., there were 240 bacteria.

n2=120; at 8:00 a.m., there were 60 bacteria.

2n=120; at 8:00 a.m., there were 60 bacteria.

The correct equation that represents the number of bacteria, n, at 8:00 a.m is 2n=120. This means that at 8:00 a.m, there were 60 bacteria.

To solve this problem, we need to understand that the culture of bacteria doubles every hour. So, from 9:00 a.m. to 8:00 a.m. (a span of 1 hour), the bacteria would have doubled.

Given that there were 120 bacteria at 9:00 a.m., we need to find the number of bacteria at 8:00 a.m. We can set up an equation to represent this situation:

n = number of bacteria at 8:00 a.m.

Since the bacteria double every hour, we can say that:

n = 2 * (number of bacteria at 9:00 a.m.)

Plugging in the known value of 120 for the number of bacteria at 9:00 a.m., we get:

n = 2 * 120

Simplifying the equation, we find that:

n = 240

So, the equation that represents the number of bacteria, n, at 8:00 a.m. is 2n = 120. And at 8:00 a.m., there were 240 bacteria.