Last year, lein earned $1,600 more than her husband. together they earned $48,100. how much did each of them earn?

Lein earned $25,650
Her husband earned $22,450

The probability will be the area under the normal distribution  from 24 to 32.

We normalize these so we can use the standard normal distribution





Typically we'd just use a computer to tell us the integral of the standard normal from -1 to 5/3.  In the old days we'd use the z table.  It tells us the normal integral from 0 to positive z.

We know the integral of the Gaussian from -1 to 1 standard deviation is 68%; from the z table we see the probability from 0 to 1 is half that, 0.34134.  That will also be the integral from -1 to 0. 

The z table says the integral from 0 to 5/3, 1.67, is 0.45254.

So our total probability, integral from -1 to 5/3, is

 

That's really from z=-1 to z=+1.67 so likely a bit off in the last couple digits.