What's the difference between subtracting the quotient of 1 / 5 / 6 / 7 from the reciprocal of 1 / 2 / 7? I have the wrong number. Division, not division

What's the difference between subtracting the quotient of 1 / 5 / 6 / 7 from the reciprocal of 1 / 2 / 7?
1 ／ 1 and 2 / 7-1 and 1 / 5 ／ 6 / 7
=7/9-7/5
=28/45

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