what proportion of the values in the population does not lie between the two z scores indicated on the diagram???
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Using the Z-table find the values for the two z numbers on the graph:
Z= -1.25 = 0.1056
Z= 0.80 = 0.7881
Subtract the two values:
0.7881 - 0.1056 = 0.6825
Now subtract the difference from 1:
1 - 0.6825 = 0.3175
The answer is B.