Answer:
14.3 km (1 d.p.)
Step-by-step explanation:
To find the <u>mean</u>, divide the sum of all data values by the total number of data values.
If Mark ran a mean distance of 13.2 km in five days, we can use the mean distance for each of the 5 days in our calculation.

Cookie Cake is in the form of a circle.
Radius of circle = 1/2 * diameter of circle = 1/2*13=13/2=6.5 in
Thus the Area of the circle = 
= 

Area of a fourth of the Cookie cake 
Circumference = 2 x pi x radius
2 x pi x 4 = 25.13 yards
(correct to 2 decimal places)
Hope this helps!!
This is an equation involving x alone, so the most you can do is solve it:

Answer:
There is a 0.82% probability that a line width is greater than 0.62 micrometer.
Step-by-step explanation:
Problems of normally distributed samples can be solved using the z-score formula.
In a set with mean
and standard deviation
, the zscore of a measure X is given by

After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X. The sum of the probabilities is decimal 1. So 1-pvalue is the probability that the value of the measure is larger than X.
In this problem
The line width used for semiconductor manufacturing is assumed to be normally distributed with a mean of 0.5 micrometer and a standard deviation of 0.05 micrometer, so
.
What is the probability that a line width is greater than 0.62 micrometer?
That is 
So



Z = 2.4 has a pvalue of 0.99180.
This means that P(X \leq 0.62) = 0.99180.
We also have that


There is a 0.82% probability that a line width is greater than 0.62 micrometer.