In a company, 30% of the employees drink coffee, 40% of the employees drink tea and 10% of the employees drink both tea ...

Question

In a company, 30% of the employees drink coffee, 40% of the employees drink tea and 10% of the employees drink both tea and coffee. What % of employees drink neither tea nor coffee?

A. 15  B. 25  C. 40  D. 49

Accepted Answer

40% of employees drink neither tea nor coffee. This is a Venn diagram problem where the universe is 100% (the entire workforce). We are given percentages for tea drinkers, coffee drinkers, and those who drink both. Using two-set inclusion-exclusion we find the percentage who drink at least one, and the complement gives those who drink neither.