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.
The perimeter is the total length of all sides of the shape.
It is 1 meter + 1 meter + 2 meter + 2 meter = 6 meters
1 meter = 100 centimeter
6(100) = 600 centimeter
Hope this helps! :)
Answer:
a) 3/5 < 4/5
b) In general if two fractions have the same denominator, then whichever fraction has the numerator closer to its denominator will be the largest fraction.
c)
<em>or</em> 
Step-by-step explanation:
a) 3/5 < 4/5
Flip the sign and the placement of the fraction so 3/5 is less then 4/5.
b) In general if two fractions have the same denominator, then whichever fraction has the numerator closer to its denominator will be the largest fraction.
c) We need to change the denominators to a common denominator to compare the size of the two fractions:
×
= 
×
= 
The common denominators of the two fractions is 30. Comparing the two fractions:
<em>or</em> 
so we get:
<em>or</em> 
Answer:
x = -27
Step-by-step explanation: