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Okay Shmoop math people word problem for yes lena's sock

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drawer contains ten pairs of socks There's a spider living

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in one of them If lena randomly takes two pairs

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of socks from the drawer what is the probability that

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both pairs are spider free Well the probability of an

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event is the ratio of desired outcomes Two possible outcomes

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right desired over possible Our personal desired outcome would be

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zero spiders taking up residence in our sock drawer but

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well lena's a live and let spider live type of

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gal Start with the first pair of socks There are

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nine desired outcomes and you know pairs of socks with

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no spider and ten possible outcomes She could pick any

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of the ten pairs of socks right None of restricted

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So there's a nine in ten chance that the first

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pair has no spider Well now that she's picked the

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first pair of socks there are nine pairs left and

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eight of these nine pairs don't have the spider The

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probability that she picks one of these is eight over

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nine Well these air too dependent events because the probability

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of picking the sock with the spider on the second

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draw changes after the first selection right The denominator shrinks

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the formula for calculating the probability of two dependent events

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lp of times p f b once a has occurred

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is pf and be well to find the probability that

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both bears are spider free Apply this formula to the

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two probabilities and we get nine tense times eight nine

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switches seventy two over ninety which is same as eight

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over ten or eighty percent So yeah those air Fairly

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decent odds They're not decent enough to keep us from

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checking our socks for spiders though forever and ever but 00:01:42.872 --> [endTime] well they're decent enough No

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