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36 votes
36 votes
Please solve this equation: 3 + 4 = 21; 2 + 5 = 14; 7 + 7 = 98; 8 + 6 = ?

User Mishbah
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2.5k points

1 Answer

25 votes
25 votes

Answer:

112

Explanation:

It appears that the relation is f(a, b) = a(a+b).

f(3, 4) = 3(3+4) = 21

f(2, 5) = 2(2+5) = 14

f(7, 7) = 7(7+7) = 98

f(8, 6) = 8(8+6) = 112

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The symbol "+" has apparently been repurposed from its usual meaning in math. It is being used as an infix operator with two arguments. We have shown the relation above as a function f with two arguments (a, b). In our definition ...

f(a, b) = a(a+b)

the symbol "+" has its usual meaning.

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Additional comment

This sort of question requires a little bit of "out of the box" thinking. It helps immensely if you're familiar with your addition and multiplication facts. Then you are in a position to recognize how the outputs may be related to the inputs.

User Gergely Szabo
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2.8k points