121 is big enough to assume normality and not worry about the t distribution. By the 68-95-99.7 rule a 95% confidence interval includes plus or minus two standard deviations. So 95% of the cars will be in the mph range

The question is a bit vague, but it seems we're being asked for the 95% confidence interval on the average of 121 cars. The 121 is a hint of course.
The standard deviation of the average is in general the standard deviation of the individual samples divided by the square root of n:

So repeating our experiment of taking the average 121 cars over and over, we expect 95% of the averages to be in the mph range

That's probably the answer they're looking for.
Answer: Perimeter = 40
Area = 204
Step-by-step explanation:
Perimeter is the sum of all the sides:
11 + 12 + 17 = 40
The area of a triangle is 1/2 base x height
1/2( 17 x 24)
1/2( 408) = 204
<em>9/20+5/12=14/32/2 equals a over all 7/16</em>
Answer:
1/2 < 2/3
Step-by-step explanation:
1/2 = .5 in decimal form while 2/3 is .6 repeating in decimal form
Answer:
5:9 If that's what you meant
Step-by-step explanation: