Question

NEED HELP NOW!! WILL GIVE FAN AND MEDAL!!





A set of data has a normal distribution with a mean of 5.1 and a standard deviation of 0.9. What percent of this data will be greater than 6.9? Express your answer as a percent rounded to the nearest tenth.











1.2%










3.2%










2.5%










4.7%

Answer 1

@iGreen
@mathmate

Answer 2

Is this an online exam?

Answer 3

yes, I don't understand it, this whole assignment is on this type of work

Answer 4

The probability of data LESS than 6.1 is given in normal distribution tables for the value of Z=(6.1-mean)/std-dev.
If you don't have a textbook, look up the table at:
https://www.stat.tamu.edu/~lzhou/stat302/standardnormaltable.pdf

The probability of data MORE than 6.1 is the 100% - the probability you got above.

Answer 5

By the way, none of the answer is correct. One of them is close.

Answer 6

Did you study the drawing above, and calculated Z?

Answer 7

is it 4.7 ?

Answer 8

Nope.
Did you calculate Z=(6.9-5.1)/0.9 ? Don't forget the parentheses!

Answer 9

its 2

Answer 10

@mathmate

Answer 11

Right!
Now look up the table of normal distribution to find the probability for Z=2.

Answer 12

If one normal distribution has a standard deviation of 5, and another has a standard deviation of 25, both still contain 68% of their values within one standard deviation.











True










False

@mathmate

Answer 13

Are the Z values the same?
If they are the same, then they contain the same percentage of data within one standard deviation, if not, they don't.