Calculate the relative frequency of the fifth class. Determine your answer as a simplified fraction

To find the relative frequency of the first class we first need to find its frequency, to help us do this we order the data which is shown below:
1047, 1052, 1081, 1161, 1172, 1214, 1222, 1231, 1268, 1307, 1313, 1329, 1330, 1332, 1343, 1402, 1402, 1412, 1421, 1447, 1455
The fifth class is made of the values from 1320 to 1389, we notice that the frequency of this class is 4. Now, the relative frequency is given by:
[tex]\frac{\text{ frequency of class}}{\text{ total frequency}}[/tex]Then we have:
[tex]\frac{4}{21}[/tex]Therefore, the relative frequency of the fifth class is 4/21