(II) The Normal Probability Density:

and from the table that gives a z = 0.84. So on the standard normal, there is 20% probability to the right of z=0.84 and 80% below that value. so convert this to units of our original distribution. rearranging the equation, z = (x - μ)/ σ , to solve for x, we get. x = z σ+ μ so z = 0.84 x 2+ 10 = 11.68 ................
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