This question still doesn't make any sense, unfortunately.
Answer: 1.2x
Step-by-step explanation:
Profit = Selling price - Cost
She bought the stock at a cost of x dollars
Her profit was 20% of that, which is 0.2x dollars
Selling price = Profit + Cost = x + 0.2x = 1.2x
15.66 is what I got in my calculator if you turn %65 into .65
Answer:
Relative frequency:

The most serious threat to aviation safety is, according to this data, "mechanical failures". It can be improved by more rigorous inspection and better maintenance policies and execution.
Step-by-step explanation:
We have the data for fatal plane crashes. The sum of plane crashes is
We can calculate the relative frequency as:

We can see that the most frequent cause is "mechanical problems", with a relative frequency of 0.45.