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IFactorial expressionsEvaluate.(4!6!)/(2!5!)Simplify your answer as much as possible.I need help with this math problem.

IFactorial expressionsEvaluate.(4!6!)/(2!5!)Simplify your answer as much as possible-example-1
User Ifreak
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1 Answer

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Step-by-step explanation

The factorial of an integer is given by the product of all the integers that are equal or smaller than it. For example, the factorial of 4 is:


4!=1\cdot2\cdot3\cdot4

We must find the value of the following expression with factorials:


(4!\cdot6!)/(2!\cdot5!)

The first thing that we can do is expand the four factorials in the expression:


(4!\cdot6!)/(2!\cdot5!)=(1\cdot2\cdot3\cdot4\cdot1\cdot2\cdot3\cdot4\cdot5\cdot6)/(1\cdot2\cdot1\cdot2\cdot3\cdot4\cdot5)

All the numbers on both the numerator and the denominator are multiplying. This means that if a number appears in the numerator and in the denominator it can be simplified. For example 1 appears twice in the numerator and twice in the denominator so it can be simplified:


(1\cdot2\cdot3\cdot4\cdot1\cdot2\cdot3\cdot4\cdot5\cdot6)/(1\cdot2\cdot1\cdot2\cdot3\cdot4\cdot5)=(1\cdot1)/(1\cdot1)\cdot(2\cdot3\cdot4\cdot2\cdot3\cdot4\cdot5\cdot6)/(2\cdot2\cdot3\cdot4\cdot5)=(2\cdot3\cdot4\cdot2\cdot3\cdot4\cdot5\cdot6)/(2\cdot2\cdot3\cdot4\cdot5)

2 appears twice in both the numerator and the denominator so it can be simplified:


(2\cdot3\cdot4\cdot2\cdot3\cdot4\cdot5\cdot6)/(2\cdot2\cdot3\cdot4\cdot5)=(3\cdot4\cdot3\cdot4\cdot5\cdot6)/(3\cdot4\cdot5)

We have a 3, a 4 and a 5 in the denominator so we can simplify them with a 3, a 4 and a 5 of the numerator:


(3\cdot4\cdot3\cdot4\cdot5\cdot6)/(3\cdot4\cdot5)=(3\cdot4\cdot5)/(3\cdot4\cdot5)\cdot(3\cdot4\cdot6)/(1)=3\cdot4\cdot6=72Answer

Then the answer is 72.

User Darryl Young
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