[ttt1293]

The average height of flowering cherry trees in a nursery is 11 feet. If the heights are normally distributed with a stand deviation of 1.6 feet, find the probabilty that a tree is less than 13 feet.

[justcurious55]

This sounds like a homework question. We won't do your homework for you. You've got to put some effort in if you want help.

[ttt1293]

this sounds like a homework question. we won't do your homework for you. you've got to put some effort in if you want help.

Not asking for it to be done for me but I'm totally new to statistics and I struggle with word problems. Just looking for some dorections but thanks anyway.

[Unknown008]

Standardize your values to the z value.



Then, look up for the probability of that z score in your z table. Be careful of what probability you are looking for! Better get a quick sketch of the bell shaped curve, and shade the area you are looking for.

[morgaine300]

Better get a quick sketch of the bell shaped curve, and shade the area you are looking for.

That's about the best advice you could get. Draw your curve and draw a z line underneath. Your standard deviation is 1.6 so that's the distance to the first notch, etc. You can easily see that 13 is a bit over 1 deviation. A z-score is how many standard deviations. i.e. how many 1.6's away from the mean is 13? So you're looking for the same point on the z line, cause that's "standardized" which is what your z equation will give you.

You want less than, so you're going left of the red line. So look that up on your z chart.