Solve the Mystery: What is 9 times 7?

  • Context: High School 
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SUMMARY

The discussion revolves around a mathematical riddle that challenges conventional multiplication. Participants explore a pattern where the product of two numbers is calculated, and then the difference between the digits of the product is taken to derive a new value. Specifically, for the multiplication of 9 times 7, the calculation yields 63, and the difference between the digits (6 and 3) results in 3. This method is confirmed through examples provided in the discussion.

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bbg5000
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It's like a riddle thinger..

If 9 times 9 is 7
10 times 9 is 9
10 times 8 is 8
8 time 8 is 2

What is 9 times 7 ?

It says to "Think mathematically. There is a pattern of calculating involved."

Anybody got any idea what this is? What the answer is??
 
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Multiply the numbers (using "normal" multiplication), then take the difference between the digits.

9 * 9 = 81 and 8 - 1 = 7.
10 * 9 = 90 and 9 - 0 = 9.
10 * 8 = 80 and 8 - 0 = 8.
8 * 8 = 64 and 6 - 4 = 2.

Since 9 * 7 = 63, the answer you're looking for is probably 6 - 3 = 3.
 
Wow.. I never saw that. Thanx
 
Originally posted by bbg5000
It says to "Think mathematically...

Utter nonsense.
 

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