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Algebra Difficulty 2.5 Junior Find the answer Canada

Tanis looked at her watch and noticed that, at that moment, it was $8x$ minutes after 7:00 a.m. and $7x$ minutes before 8:00 a.m. for some value of $x$ . What time was it at that moment?

Pick one

Solution

The number of minutes between 7:00 a.m. and the moment when Tanis looked at her watch was $8x$ , and the number of minutes between the moment when Tanis looked at her watch and 8:00 a.m. was $7x$ .

The total number of minutes between 7:00 a.m. and 8:00 a.m. is 60.

Therefore, $8x+7x=60$ and so $15x=60$ or $x=4$ .

The time at that moment was $8x = 32$ minutes after 7:00 a.m., and so was 7:32 a.m. (We note that 7:32 a.m. is $28=7x$ minutes before 8:00 a.m.)

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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.