The Number Puzzle
I am thinking of a number. If I multiply this number by 3 and then subtract 7, the result is 20.
What is the number I am thinking of?
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We need to work backwards from the result to that we can get to the initial number that they were thinking of.
ReplyDeleteInstead of subtracting 7 from 20, we must add 7 to 20 to get 27
Then we need to divide by 3 rather than multiply by 3 to get 27/3 = 9
Therefore, 9 is the number that they were thinking of