A. The "z-score" for 107 is (107 - 85)/11 = 2.0. Using a normal distribution table, the probability of (z > 2.0) is 0.0228. If your table shows 0.9772 next to z = 2, that's P(z<2), so you subtract it from 1 to get P(z>2). So the answer is 0.0228 or 2.28%.
B. Look at the face of the normal distribution table to find 0.8900 (which only 11% exceeds!). I find it's between 1.22 and 1.23, perhaps around 1.226. So now with the "z-score" of 1.226, I have
1.226 = (X - 85)/11 => X = 98.5. Only the top 11% exceeds 98.5. It's hard to know whether the given problem is assuming count data or measure data -- that is, are non-integer values allowable?
Answers & Comments
A. The "z-score" for 107 is (107 - 85)/11 = 2.0. Using a normal distribution table, the probability of (z > 2.0) is 0.0228. If your table shows 0.9772 next to z = 2, that's P(z<2), so you subtract it from 1 to get P(z>2). So the answer is 0.0228 or 2.28%.
B. Look at the face of the normal distribution table to find 0.8900 (which only 11% exceeds!). I find it's between 1.22 and 1.23, perhaps around 1.226. So now with the "z-score" of 1.226, I have
1.226 = (X - 85)/11 => X = 98.5. Only the top 11% exceeds 98.5. It's hard to know whether the given problem is assuming count data or measure data -- that is, are non-integer values allowable?