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The numbers 2 and 5 are the only two prime numbers that end in 2 or 5. What is the rationale for the following groups of numbers?
3 17 31 47 61
7 19 37 49 67
11 23 41 53 71
13 29 43 59 73
3 17 31 47 61
7 19 37 49 67
11 23 41 53 71
13 29 43 59 73
Answer
The numbers are grouped by column according to their BINGO letters (B = 1 through 15, I = 16 through 30, N = 31 through 45, G = 46 through 60, O = 61 through 75).Hide Answer Show Answer
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