Brain Teasers
Special Numbers
Group
These brain teasers rely on your ability to recognize groups of common attributes. For each of these puzzles you'll need to figure out why the words or letters are grouped as they are. Sometimes you will be asked to pick the odd-one-out or to place a new word into the correct group.Group
What number does not belong?
45
63
81
73
54
90
45
63
81
73
54
90
Answer
73. All the other numbers equal 9 through addition and are multiples of 9.4+5=9; 45=9x5
6+3=9; 63=9x7
8+1=9; 81=9x9
5+4=9; 54=9x6
9+0=9; 90=9x10
But, 7+3=10.
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Comments
Yay! My 10th teaser! Enjoy!
Hey! That was a cute one! Really nejoyed it!
Thanks. And what does nejoyed mean?
i thought it was 90 coz it the only even number
good one
good one
easy... but then my speciality is maths!
EEEEEEEEEEEEE-ZZZZZZZZZZZZZZ
I said 73 because it was prime. I didn't even notice the others were multiples of 9!!
Fun, challenging and entertaining teaser. I picked 73 and got it right. It was the only number not divisible by 9.
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