Difference between revisions of "2023 AMC 8 Problems/Problem 4"
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==Solution 1== | ==Solution 1== | ||
| − | + | First, we fill out the entire grid. We find that the four numbers are <math>39,19,23,47</math>. The numbers <math>19,23,</math> and <math>47</math> are prime, so there are <math>\boxed{\textbf{(D) }3}</math> numbers that are prime. | |
~MathFun1000 | ~MathFun1000 | ||
Revision as of 21:52, 24 January 2023
The numbers from 1 to 49 are arranged in a spiral pattern on a square grid, beginning at the center. The first few numbers have been entered into the grid below. Consider the four numbers that will appear in the shaded squares, on the same diagonal as the number 7. How many of these four numbers are prime?
Solution 1
First, we fill out the entire grid. We find that the four numbers are 
. The numbers 
and 
are prime, so there are 
numbers that are prime.
~MathFun1000
Solution 2
Fill out the entire grid to count that there are 
-apex304
