In Exercises 81–85, use a calculator's factorial key to evaluate ...

Question

In Exercises 81–85, use a calculator's factorial key to evaluate each expression. 200!/198!

Accepted Answer

Welcome back. I am so glad you're here. We are given the expression 158 factorial divided by 156 factorial. And were asked to use a calculator to evaluate the following expression. Well if you can go ahead and plug that right into your calculator, great. If you've got a calculator like mine and it doesn't have a factorial button, there is a way to simplify this before plugging it into the calculator so that we don't have to use the factorial button. We know that factorial means you're starting with the number that's given 158 in the numerator here and then you're multiplying at times every single number that comes below it. So 1 58 times 1, 57 times 1 56 etcetera all the way down to one. But we could rewrite this as 158 times times 156 factorial. And then we keep 156 factorial in the denominator. And look now we've got factors that cancel out this factorial is the same as 156 factorial in both the numerator and the denominator. So now you just have to plug into your calculator, 158 times 157. And when you do that you get an answer of 24,806 which matches with answer choice B Well done. We'll catch you on the next one

Struggling with College Algebra?

In Exercises 81–85, use a calculator's factorial key to evaluate each expression. 200!/198!

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