Which of the following statements describe an exponential relationship?

A. the temperature is increasing at the rate of 3 degrees per hour.
B. the number of bacteria is increaing at the rate of 30% per minute
C. The number of cars in the parking lot is decreasing at the rate of 5 cars per hour.
D. The price of houses in this neighborhood is increasing at the rate of $15,000 per year

Exponential relationships are dependent on the current population, A,B,D do not meet that criteria, do they?

The statement that describes an exponential relationship is:

B. The number of bacteria is increasing at the rate of 30% per minute.

In an exponential relationship, the value is increasing or decreasing at a constant rate relative to its current value. In this case, the number of bacteria is increasing by a percentage (30%) per minute, and the rate of increase is constant relative to the current number of bacteria.

To determine which of the given statements describe an exponential relationship, let's understand what an exponential relationship is. Exponential relationships occur when a quantity grows or decays at an accelerating rate, meaning its rate of change keeps increasing or decreasing over time.

A. The statement "the temperature is increasing at the rate of 3 degrees per hour" does not describe an exponential relationship because the rate of change remains constant at 3 degrees per hour. It is a linear relationship.

B. The statement "the number of bacteria is increasing at the rate of 30% per minute" does describe an exponential relationship because the rate of change is proportional to the current value. As the number of bacteria increases, the rate of increase grows larger. This is characteristic of exponential growth.

C. The statement "the number of cars in the parking lot is decreasing at the rate of 5 cars per hour" does not describe an exponential relationship because the rate of change remains constant at 5 cars per hour. It is a linear relationship.

D. The statement "the price of houses in this neighborhood is increasing at the rate of $15,000 per year" does not describe an exponential relationship because the rate of change remains constant at $15,000 per year. It is a linear relationship.

Therefore, the statement that describes an exponential relationship is B. "The number of bacteria is increasing at the rate of 30% per minute."