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Difference between revisions of "2019 AMC 10A Problems"

m (Problem 1)
(Problem 25)
Line 31: Line 31:
 
==Problem 24==
 
==Problem 24==
 
==Problem 25==
 
==Problem 25==
 +
For how many integers <math>n</math> between 1 and 50, inclusive, is
 +
 +
<math>\frac{(n^2-1)!}{(n!)^{n}}</math>
 +
 +
an integer? (Recall that <math>0!=1</math>.)
 +
 +
A. 31
 +
B. 32
 +
C. 33
 +
D. 34
 +
E. 35

Revision as of 16:07, 9 February 2019

Problem 1

What is the value of \[2^{\left(0^{\left(1^9\right)}\right)}+\left(\left(2^0\right)^1\right)^9?\] $\textbf{(A) } 0 \qquad\textbf{(B) } 1 \qquad\textbf{(C) } 2 \qquad\textbf{(D) } 3 \qquad\textbf{(E) } 4$

Problem 2

What is the hundreds digit of $(20!-15!)\ ?$

$\textbf{(A) }0\qquad\textbf{(B) }1\qquad\textbf{(C) }2\qquad\textbf{(D) }4\qquad\textbf{(E) }5$

Problem 3

Problem 4

Problem 5

Problem 6

Problem 7

Problem 8

Problem 9

Problem 10

Problem 11

Problem 12

Problem 13

Problem 14

Problem 15

Problem 16

Problem 17

Problem 18

Problem 19

Problem 20

Problem 21

Problem 22

Problem 23

Problem 24

Problem 25

For how many integers $n$ between 1 and 50, inclusive, is

$\frac{(n^2-1)!}{(n!)^{n}}$

an integer? (Recall that $0!=1$.)

A. 31 B. 32 C. 33 D. 34 E. 35