Brain Teasers
7, 97, 997
Series
Series teasers are where you try to complete the sequence of a series of letters, numbers or objects.Series
1 = 7
2 = 97
3 = 997
4 = 9973
5 = ?
What number should replace the question mark above?
Your choices are:
A) 99991
B) 99997
C) 99919
D) 99979
2 = 97
3 = 997
4 = 9973
5 = ?
What number should replace the question mark above?
Your choices are:
A) 99991
B) 99997
C) 99919
D) 99979
Answer
The answer is A) 99991.The number on the right is the highest prime number with the number of digits equal to the number on the left. In other words, 7 is the highest 1-digit prime number, 97 is the highest 2-digit prime number, and so on.
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