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O PROBABILITY AND STATISTICSFactorial expressionsEvaluate.8!5!9!2!Simplify your answer as much as possible.I need help math problems.

User Alexandre Heinen
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1 Answer

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Hello!

This is an exercise about factorials. To solve it, we have to expand the expressions, look:


(8!\cdot5!)/(9!\cdot2!)

Let's rewrite 9! in the denominator:


\frac{\cancel{8!}\cdot5!}{9\cdot\cancel{8!}\cdot2!}=(5!)/(9\cdot2!)

Note that as we have 8! in the numerator and denominator, we can cancel it.

Now, let's expand the expression 5!:


\frac{5\cdot4\operatorname{\cdot}3\operatorname{\cdot}\cancel{2!}}{9\operatorname{\cdot}\cancel{2!}}=\frac{5\operatorname{\cdot}4\operatorname{\cdot}3}{9}=(60)/(9)=(20)/(3)

In the same way, we can cancel 2!.

Simplifying the fractions, we will obtain the result as 20/3.

Answer:


(20)/(3)