Question

Last years' survey of blood type on 100 Ethiopian servals that 20 peoples have blood type A, 30 peoples have type B, 40 peoples have type O and the remaining have type AB. What is the probability of getting an Ethiopian with blood type A and AB?

Answer 1

30%.

Explanation:

The probability of getting an Ethiopian with blood type A is
`(20)/(100) \cdot 100%%`, which equals to 20%, while the probability of getting an Ethiopian with blood type AB is
`(100-40-30-20)/(100) \cdot 100%`, which equals to
`(10)/(100) \cdot 100%` and hence 10%. Therefore, just add the two probabilities together to get 20% +10% = 30%.

Hope this helped!