Subtract 21/6 from 7/80, Solve 7/80

Subtract 21/6 from 7/80

1^st number: 7/80, 2^nd number: 3 3/6

7/80 - 21/6 is -273/80.

Find the least common denominator or LCM of the two denominators:
LCM of 80 and 6 is 240

Next, find the equivalent fraction of both fractional numbers with denominator 240
For the 1st fraction, since 80 × 3 = 240,
7/80 = 7 × 3/80 × 3 = 21/240
Likewise, for the 2nd fraction, since 6 × 40 = 240,
21/6 = 21 × 40/6 × 40 = 840/240
Subtract the two like fractions:
21/240 - 840/240 = 21 - 840/240 = -819/240
After reducing the fraction, the answer is -273/80

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