By 32,760 different ways can a researcher select 4 rats from 15 rats and assign each to a different test .
<u>Step-by-step explanation:</u>
We need to find How many different ways can a researcher select 4 rats from 15 rats and assign each to a different test.Let's find out:
We will use Permutation here : As we will chose 4 rats out of 15 rats , order will be considered which will make this as a permutation problem . Formula for permutation is given by :
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According to question , we have
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Therefore , By 32,760 different ways can a researcher select 4 rats from 15 rats and assign each to a different test .