Subtract 45/7 from 7/21
1st number: 7/21, 2nd number: 6 3/7
721 - 457 is -12821.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 7 is 21
Next, find the equivalent fraction of both fractional numbers with denominator 21 - For the 1st fraction, since 21 × 1 = 21,
721 = 7 × 121 × 1 = 721 - Likewise, for the 2nd fraction, since 7 × 3 = 21,
457 = 45 × 37 × 3 = 13521 - Subtract the two like fractions:
721 - 13521 = 7 - 13521 = -12821
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