Question is in the description below.

Question

speed of automobiles on a certain stretch of freeway at 11:00 PM are normally distributed with mean 65 mph. Twenty percent of the cars traveling at speeds between 55 and 65. What percentage of the cars is going faster than 75 mph? Explain your reasoning

Answer 1

Then 20% of them go between 65 and 75.

That leaves 60% for both tails.

So 30% faster than 75