A box contains 30 bolts and 40 nuts. Half of the bolts and half of the nuts are rusted. If two items are drawn at random, what is the probability that either both are rusted or both are bolts?

Explanation

Given there are total 30 bolts and 40 nuts.

Half the bolts and nuts are rusted


∴ Rusted bolts `= 15`


Rusted nuts `= 20`


Total number of rusted items =`15+20=35`

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