I do not understand how to put the answer in the form of fraction. A clinic took

Question

I do not understand how to put the answer in the form of fraction.

A clinic took temperature readings of 250 flu patients over a weekend and discovered the temperature distribution to be Gaussian, with a mean of 101.70°F and a standard deviation of 0.5630. Use this normal error curve area table to find the following values. (a) What is the fraction of patients expected to have a fever greater than 103.39°F?

(b) What is the fraction of patients expected to have a temperature between 101.59°F and 102.21°F?

Ordinate and Area for a Normal Error Curve

z = (x – )/
The area refers to the area between z = 0 and z = the table value.

|z| y Area 0.0 0.3989 0.0000 0.1 0.3970 0.0398 0.2 0.3910 0.0793 0.3 0.3814 0.1179 0.4 0.3683 0.1554 0.5 0.3521 0.1915 0.6 0.3332 0.2258 0.7 0.3123 0.2580 0.8 0.2897 0.2881 0.9 0.2661 0.3159 1.0 0.2420 0.3413 1.1 0.2179 0.3643 1.2 0.1942 0.3849 1.3 0.1714 0.4032 1.4 0.1497 0.4192 1.5 0.1295 0.4332 1.6 0.1109 0.4452 1.7 0.0941 0.4554 1.8 0.0790 0.4641 1.9 0.0656 0.4713 2.0 0.0540 0.4773 2.1 0.0440 0.4821 2.2 0.0355 0.4861 2.3 0.0283 0.4893 2.4 0.0224 0.4918 2.5 0.0175 0.4938 2.6 0.0136 0.4953 2.7 0.0104 0.4965 2.8 0.0079 0.4974 2.9 0.0060 0.4981 3.0 0.0044 0.498650 3.1 0.0033 0.499032 3.2 0.0024 0.499313 3.3 0.0017 0.499517 3.4 0.0012 0.499663 3.5 0.0009 0.499767 3.6 0.0006 0.499841 3.7 0.0004 0.499904 3.8 0.0003 0.499928 3.9 0.0002 0.499952 4.0 0.0001 0.499968 0 0.5

Explanation / Answer

a)

We first get the z score for the critical value. As z = (x - u) / s, then as          
          
x = critical value =    103.39      
u = mean =    101.7      
          
s = standard deviation =    0.563      
          
Thus,          
          
z = (x - u) / s =    3.001776199      
          
Thus, using a table/technology, the right tailed area of this is          
          
P(z >   3.001776199   ) =    0.001342047 [answer]

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b)

We first get the z score for the two values. As z = (x - u) / s, then as          
x1 = lower bound =    101.59      
x2 = upper bound =    102.21      
u = mean =    101.7      
          
s = standard deviation =    0.563      
          
Thus, the two z scores are          
          
z1 = lower z score = (x1 - u)/s =    -0.195381883      
z2 = upper z score = (x2 - u) / s =    0.905861456      
          
Using table/technology, the left tailed areas between these z scores is          
          
          
P(z < z2) =    0.817495406      
          
Thus, the area between them, by subtracting these areas, is          
          
P(z1 < z < z2) =    0.817495406   [answer]  

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