Subtract 49/90 from 72/21
1st number: 3 9/21, 2nd number: 49/90
72/21 - 49/90 is 1817/630.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 21 × 30 = 630,
72/21 = 72 × 30/21 × 30 = 2160/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
49/90 = 49 × 7/90 × 7 = 343/630 - Subtract the two like fractions:
2160/630 - 343/630 = 2160 - 343/630 = 1817/630 - In mixed form: 2557/630
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