If you would like to know Johnathan's average speed in miles per hour, you can calculate this using the following steps:
3 2/3 = 11/3 miles ... 7/8 hour
x miles = ? ... 1 hour
11/3 * 1 = 7/8 * x
11/3 = 7/8 * x
x = 11/3 * 8/7
x = 88/21
x = 4 4/21 miles
The correct result would be 4 4/21 miles per hour.
The sum of the rational expression is
X=4
If a random sample of 20 persons weighed 3,460, the sample mean x-bar would be 3460/20 = 173 pounds.
The z-score for 173 pounds is given by:

Referring to a standard normal distribution table, and using z = 0.66, we find:

Therefore

The answer is: 0.2546