Subtract 18/30 from 72/21
1st number: 3 9/21, 2nd number: 18/30
72/21 - 18/30 is 99/35.
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,
72/21 = 72 × 10/21 × 10 = 720/210 - Likewise, for the 2nd fraction, since 30 × 7 = 210,
18/30 = 18 × 7/30 × 7 = 126/210 - Subtract the two like fractions:
720/210 - 126/210 = 720 - 126/210 = 594/210 - After reducing the fraction, the answer is 99/35
- In mixed form: 229/35
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