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, 2016

Number theory Difficulty 1.1 Junior Find the answer Canada

Which of the following is a multiple of 7?

Pick one

Solution

Solution 1

A number is a multiple of 7 if it is the result of multiplying 7 by an integer.

Of the answers given, only 77 results from multiplying 7 by an integer, since $77=7\times11$ .

Solution 2

A number is a multiple of 7 if the result after dividing it by 7 is an integer.

Of the answers given, only 77 results in an integer after dividing by 7, since $77\div7=11$ .

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Source: CEMC, University of Waterloo, licensed CC-BY-NC-4.0. Statement reproduced verbatim; metadata (topic, difficulty) added by this project.