Subtract 21/80 from 21/3, Solve 7 0/3

Subtract 21/80 from 21/3

1^st number: 7 0/3, 2^nd number: 21/80

21/3 - 21/80 is 539/80.

Find the least common denominator or LCM of the two denominators:
LCM of 3 and 80 is 240

Next, find the equivalent fraction of both fractional numbers with denominator 240
For the 1st fraction, since 3 × 80 = 240,
21/3 = 21 × 80/3 × 80 = 1680/240
Likewise, for the 2nd fraction, since 80 × 3 = 240,
21/80 = 21 × 3/80 × 3 = 63/240
Subtract the two like fractions:
1680/240 - 63/240 = 1680 - 63/240 = 1617/240
After reducing the fraction, the answer is 539/80
In mixed form: 659/80

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