Question 1180195
z=(x-mean)/sd
z lower=(1797-2243)/199=-2.24
z upper=163/199=0.82
the probability is 0.7813
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check on calculator with 2 VARS 2 normalcdf (1797,2406,2243,199)ENTER=0.7811, which is slightly more accurate, since the z-values are not rounded until the calculation. This is obtained with 3 decimal places for z.