A certain bacteria doubles every day. If there were 400 in the original culture, how many would be present after 3 days?

well, it will double three times, right? So, that's 8 times the original amount...

To find the number of bacteria after 3 days, we'll need to know the growth rate. Since the bacteria double every day, the growth rate is 2.

To calculate the number of bacteria after 3 days, we can use the formula:

Number of bacteria after n days = initial number of bacteria * (growth rate)^(number of days)

In this case, the initial number of bacteria is 400, the growth rate is 2, and the number of days is 3. Plugging in these values, we get:

Number of bacteria after 3 days = 400 * (2)^3

Simplifying:

Number of bacteria after 3 days = 400 * 8

Number of bacteria after 3 days = 3200

Therefore, there would be 3200 bacteria present after 3 days.

To solve this problem, we can use the formula for exponential growth: Final amount = Initial amount × (growth rate)^(number of time periods).

In this case, the initial amount is 400 bacteria, the growth rate is 2 (since the bacteria double every day), and the number of time periods is 3 days.

Plugging these values into the formula, we get:

Final amount = 400 × (2)^3

Calculating 2 raised to the power of 3, we get:

Final amount = 400 × 8

Multiplying 400 by 8, we find that:

Final amount = 3200

Therefore, after 3 days, there will be 3200 bacteria present in the culture.