AlgebraDifficulty 4.7AIMEFind the answerNetherlands
We order the positive odd integers as follows:
column 1
column 2
column 3
column 4
column 5
column 6
...
row 1
1
3
11
13
29
31
...
row 2
5
9
15
27
33
...
row 3
7
17
25
35
...
row 4
19
23
37
...
row 5
21
39
...
row 6
41
...
...
...
For each odd number we can determine in which row and column it is placed. For example, the number 35 is placed in row 3 and column 4. What number is placed in row 22 and column 24? A) 2021 B) 2023 C) 2025 D) 2027 E) 2029
This was a multiple-choice question, but the options didn't survive into the
source we have. The answer given is D, and the solution
below works it through.
Solution
D) 2027
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Source: MathNet,
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