2020 AMC 8 Problems/Problem 12
Revision as of 00:58, 18 November 2020 by Icematrix2 (talk | contribs)
For positive integers , the notation
denotes the product of the integers from
to
. What value of
satisfies the following equation?
Solution 1
Notice that =
and we can combine the numbers to create a larger factorial. To turn
into
we need to multiply
by
which equals to
Therefore, we have
We can cancel the
since we are multiplying them on both sides of the equation.
We have
From here, it is obvious that
-iiRishabii