Difference between revisions of "2022 AMC 10B Problems/Problem 6"
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~MRENTHUSIASM | ~MRENTHUSIASM | ||
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| + | ==Solution 2 (If you don't see the above/are running low on time)== | ||
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| + | Note that it's obvious that 121 is divisible by 11 and 11211 is divisible by 3; therefore, since this an AMC 10 problem 6, we may safely assume that we do not need to check two digit prime divisibility or use obscure theorems; therefore, the answer is <math>\boxed{\textbf{(A)} 0}.</math> | ||
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| + | ~Dhillonr25 | ||
== See Also == | == See Also == | ||
{{AMC10 box|year=2022|ab=B|num-b=5|num-a=7}} | {{AMC10 box|year=2022|ab=B|num-b=5|num-a=7}} | ||
{{MAA Notice}} | {{MAA Notice}} | ||
Revision as of 22:58, 17 November 2022
Contents
Problem
How many of the first ten numbers of the sequence 
are prime numbers?
Solution
The 
th term of this sequence is
It follows that the terms are
Therefore, there are 
prime numbers in this sequence.
~MRENTHUSIASM
Solution 2 (If you don't see the above/are running low on time)
Note that it's obvious that 121 is divisible by 11 and 11211 is divisible by 3; therefore, since this an AMC 10 problem 6, we may safely assume that we do not need to check two digit prime divisibility or use obscure theorems; therefore, the answer is 
~Dhillonr25
See Also
| 2022 AMC 10B (Problems • Answer Key • Resources) | ||
| Preceded by Problem 5 |
Followed by Problem 7 | |
| 1 • 2 • 3 • 4 • 5 • 6 • 7 • 8 • 9 • 10 • 11 • 12 • 13 • 14 • 15 • 16 • 17 • 18 • 19 • 20 • 21 • 22 • 23 • 24 • 25 | ||
| All AMC 10 Problems and Solutions | ||
The problems on this page are copyrighted by the Mathematical Association of America's American Mathematics Competitions. 
