Subtract 72/30 from 81/21
1st number: 3 18/21, 2nd number: 2 12/30
81/21 - 72/30 is 51/35.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 30 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 21 × 10 = 210,
81/21 = 81 × 10/21 × 10 = 810/210 - Likewise, for the 2nd fraction, since 30 × 7 = 210,
72/30 = 72 × 7/30 × 7 = 504/210 - Subtract the two like fractions:
810/210 - 504/210 = 810 - 504/210 = 306/210 - After reducing the fraction, the answer is 51/35
- In mixed form: 116/35
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