1 inch = 12 miles
so 6 1/2 inches (or 6.5 inches) = 6.5 * 12 = 78 miles <===
<h3>
Answer: 83.85%</h3>
This value is approximate.
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Explanation:
Let's compute the z score for x = 40
z = (x-mu)/sigma
z = (40-47)/7
z = -1
We're exactly one standard deviation below the mean.
Repeat these steps for x = 68
z = (x-mu)/sigma
z = (68-47)/7
z = 3
This score is exactly three standard deviations above the mean.
Now refer to the Empirical Rule chart below. We'll add up the percentages that are between z = -1 and z = 3. This consists of the two pink regions (each 34%), the right blue region (13.5%) and the right green region (2.35%). These percentages are approximate.
34+34+13.5+2.35 = 83.85
<u>Roughly 83.85%</u> of the one-mile roadways have between 40 and 68 potholes.
Change each mixed fraction to improper
3 2/5 = 15/5 + 2/5 = 17/5
9 1/10 = 90/10 + 1/10 = 91/10
Find a common denominator. Multiply 2 to both numerator and denominator of 17/5
17/5(2/2) = 34/10
34/10 + 91/10 = 125/10
125/10
Simplify. Divide
125/10 = 12.5
12.5 is your answer
hope this helps