A. From a table of values, we find that the area from 0 to .94 is .32639, so the area from -Infinity to +.94 will be 0.5 + 0.32639 = 0.82639
b. Using the same table of values, the area from 0 to .65 is found to be .24215, so the area to the right of that value will be 0.5 - 0.24215 = 0.25785
c. The area to the right of 1076 is way far out in the right tail, effectively 0. It would take a special approximation to determine the value of that.
Perhaps you mean "to the right of 1.076". If so, that requires some interpolation between values supplied by the table. The table gives values for 1.07 and for 1.08 as 0.35769 and 0.35993, respectively. A linear interpolation between them is computed as
(p-.35769) = (1.076-1.07)(.35993-.35769)/(1.08-1.07)
p = .35769 + .6(.00224) = .35769 + .00134 = .35903
So, the area right of z=1.076 is .5 - .35903 = .14097
d. Area to the left of -.34 is the same as area to the right of +.34: .5 - .13307 = .36693.
Area to the left of .62 is .5 + .23237 = .73237.
The area between these lines is .73237 - .36693 = .36544.
You should probably use the table supplied in your text or handbook, or a computer program. Excel will make these calculations.
b. Using the same table of values, the area from 0 to .65 is found to be .24215, so the area to the right of that value will be 0.5 - 0.24215 = 0.25785
c. The area to the right of 1076 is way far out in the right tail, effectively 0. It would take a special approximation to determine the value of that.
Perhaps you mean "to the right of 1.076". If so, that requires some interpolation between values supplied by the table. The table gives values for 1.07 and for 1.08 as 0.35769 and 0.35993, respectively. A linear interpolation between them is computed as
(p-.35769) = (1.076-1.07)(.35993-.35769)/(1.08-1.07)
p = .35769 + .6(.00224) = .35769 + .00134 = .35903
So, the area right of z=1.076 is .5 - .35903 = .14097
d. Area to the left of -.34 is the same as area to the right of +.34: .5 - .13307 = .36693.
Area to the left of .62 is .5 + .23237 = .73237.
The area between these lines is .73237 - .36693 = .36544.
You should probably use the table supplied in your text or handbook, or a computer program. Excel will make these calculations.