A drawer contains 50 bolts and 150 nuts. Half of the bolts and half of the nuts are rusted. If one item is chosen at random, what is the probability that it is rusted or a bolt?

Explanation

Let A be the events of item being rusted

`P(A)=
=100/200​=1/2`​

B be the events of item is bolt

`P(B)=50/200​=1/4`
​
`P(A∩B)`=item is rusted and bolt =`25/200​=1/8`
​
`P(A∪B)
=P(A)+P(B)−P(A∩B)`

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