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Information.
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The normal distribution for young men's heights is 69 .3 inches with a standard deviation of 2 .8 inches.
00:08
These are all inches.
00:11
For young women it's 64 .5 inches and our standard deviation is 2 .5 inches.
00:19
Letting m equals men's height and w equals women's height, we can see that m and w are if if m and w are normally distributed which we're told they are then m w is also normally distributed okay so the properties mean mean and standard deviation, my ax plus ey equals a mean of x plus b times the mean of y.
01:22
So it's standard deviation of ax plus by equals the square root of the a squared times the standard deviation squared plus b squared times the standard deviation squared.
01:38
Squared.
01:38
Okay, and we'll get this.
01:48
I'm going to make that a little bit more, and that'll be 69 .3 minus 64 .8, or 5, equals 4 .8.
02:08
So the distribution is normal.
02:11
So we have a normal distribution, and our mean of m and w will be 4 .8 inches and then let's try this color.
02:31
This will equal, plugging my values in, 2 .8 squared plus 2 .5 squared and that will equal 3 .754...