380 divide by 20
it will take her 19 hours to stamp 380 letters
Answer:
The probability that the maximum speed is at most 49 km/h is 0.8340.
Step-by-step explanation:
Let the random variable<em> </em><em>X</em> be defined as the maximum speed of a moped.
The random variable <em>X</em> is Normally distributed with mean, <em>μ</em> = 46.8 km/h and standard deviation, <em>σ</em> = 1.75 km/h.
To compute the probability of a Normally distributed random variable we first need to convert the raw score of the random variable to a standardized or <em>z</em>-score.
The formula to convert <em>X</em> into <em>z</em>-score is:

Compute the probability that the maximum speed is at most 49 km/h as follows:
Apply continuity correction:
P (X ≤ 49) = P (X < 49 - 0.50)
= P (X < 48.50)

*Use a <em>z</em>-table for the probability.
Thus, the probability that the maximum speed is at most 49 km/h is 0.8340.
Given:
descends at a rate of 320 feet per minute for 3 minutes.
320 feet per minute * 3 minutes = 960 feet
Total change in altitude is 960 feet. Since it is descending, I believe it would be a negative 960 feet.
It could be anything they are both variables.
When f is greater than 82.