Suppose 80% of people can swim. Suppose 70% of people can

whistle. Suppose 55% of people can do both. What percentage of people

can swim or whistle?

95%

Step-by-step explanation:

Let the proportion who can swim be denoted by P (S) while the proportion that can whistle be denoted by P (W)

The proportion that can swim and whistle will be P (S and W)

The proportion that can swim or whistle will be P (S or W)

To get the proportion that can swim or whistle will be P (S or W), we use

P (S or W) = P (S) + P (W) - P (S and W)

Given that P (W) is 70%, P (S) is 80% and P (S andW) is 55% then

P (S or W) = 80%+70%-55%=95%