The roster form of a set is the elements listed inside brackets { }.
In this case it is easy to visualize A - B directly of the Venn diagram: when you subtract from A those elements that are also in B, the result is A - B = {4, 11, 14}.
Now take into account tha (A - B)' is the complement of (A - B), this is all the elements that are not in A - B.
Being A - B = {4, 11, 14} then to show (A - B)' you just have to list all the elements that are on the figure except 4, 11 and 14.
The result, in roster form, is (A - B)' = {1, 2, 3, 5, 6, 7, 8, 9, 10, 12, 13}
Percentile is a statistic in which the an element at a certain percentage position is determined. To calculate the percentiles accurately, it is important that the data is present in the ascending order. Percentile is an important concept in data analysis. Interestingly, 50th percentile is the median of the data. The difference between the 75th and the 25th percentile is the interquartile range. To find the 85th percentile of the data, calculate 85% of 40, which is the number of elements in the data set. 40 * 85/100 = 34. The number on the 34th position is the 85th percentile of the data. It can be observed that 89 is on the 34th position. Therefore, Option A is the answer!!!
