If I've read this correctly, it looks like this.
If that is correct, then the first step is to put the top part of the denominator over 3x
The next part is to flip a three tier fraction. I'm afraid I have to show what happens. My latex is not that strong.
What you get is
This is just about your final answer. You could write it as
Answer: 0.84134
Step-by-step explanation:
We need to find the z-score for the given information first since this will help us find the probability. The formula for this is
Z score =
We have
66 inches (the raw score)
70 inches (the population mean)
= 4 inches (the standard deviation)
This gives
Z score = =
If you use a calculator, or a Z-score table then P(x > Z) is just P(Z > -1) which gives a probability of 0.84134.