Set up hypotheses:
H0: the data follows the expected results
H1: the data does not follow the expected results
Calculate the expected results:
200*0.065 = 13
200 - 13 = 187
So the expected results are 13 and 187.
Now get the chi square test statistic:
= (19-13)^2/13 + (181-187)^2/187
Now, with df = 1 (because there are 2 categories, and df is 1 less than the number of categories), use a table (such as http://www.danielsoper.com/statcalc3/calc.aspx?id=11) to compute the p value.
p = 0.0853
Since this is above the alpha of 0.05, we do not reject H0.
Therefore, there is not enough evidence to conclude that the last initial quantity is different than expected if matched randomly.
Let me know if you have any questions on this, and if you're set, thanks for choosing a high rating.