Answer:
D
Step-by-step explanation:
1. Remind that
Here you can use trigonometric table to find the value of , or you can remind that
and
because special right triangle 45°-45°-90° is isosceles (with congruent oppposite and adjacent legs) and the ratio between the opposite leg and adjacent leg is equal to 1.
2. Now
because
Answer:
the standard deviation of the speeds of cars travelling on California freeways is 6.0 miles per hour
Step-by-step explanation:
The computation of the standard deviation of the speeds of cars is shown below;
The z score for the top 1% is 2.326
So,
= (75 - 61) ÷ standard deviation = 2.326
Standard deviation is
= 14 ÷ 2.326
= 6.0 miles per hour
Hence, the standard deviation of the speeds of cars travelling on California freeways is 6.0 miles per hour
