Answer:
Observed: 145
Expected: 107.2
Explanation:
to get the observed frequency, we simply look at the value in the column. In this case, it is 145 for the yellow group.
To get the expected frequency, we use the formula:
n equals s a m p l e space s i z e equals 536
p equals h y p o t h e s i z e d space p r o p o r t i o n equals 20 percent sign equals 0.2
E x p e c t e d space F r e q u e n c y equals n times p equals 536 times 0.2 equals 107.2