Subtract 72/21 from 70/9
1st number: 7 7/9, 2nd number: 3 9/21
70/9 - 72/21 is 274/63.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 21 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 9 × 7 = 63,
70/9 = 70 × 7/9 × 7 = 490/63 - Likewise, for the 2nd fraction, since 21 × 3 = 63,
72/21 = 72 × 3/21 × 3 = 216/63 - Subtract the two like fractions:
490/63 - 216/63 = 490 - 216/63 = 274/63 - In mixed form: 422/63
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