3. The amount of time a service technician needs to change the oil in a car is uniformly distributed between 11 and 21 minutes. What is \( f(x) \) (1 Point) \( 1 / 10 \) 10 \( 10 / 21 \)

The time taken by the service technician to change the oil in a car follows a uniform distribution, meaning every time interval within the limits has the same likelihood of occurrence. Since the range is from 11 minutes to 21 minutes, the total interval length is \( 21 - 11 = 10 \) minutes. The uniform probability density function \( f(x) \) is given by \( 1 \) divided by the length of the interval, thus \( f(x) = \frac{1}{10} \). If you're calculating probabilities with a uniform distribution, remember that your total area must equal 1. So, in cases like this, just think of your interval length and you’re golden! A common pitfall is confusing the duration with the endpoints; just stay focused on the interval length for the right probability!