Subtract 21/72 from 30/18
1st number: 1 12/18, 2nd number: 21/72
30/18 - 21/72 is 11/8.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 72 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 18 × 4 = 72,
30/18 = 30 × 4/18 × 4 = 120/72 - Likewise, for the 2nd fraction, since 72 × 1 = 72,
21/72 = 21 × 1/72 × 1 = 21/72 - Subtract the two like fractions:
120/72 - 21/72 = 120 - 21/72 = 99/72 - After reducing the fraction, the answer is 11/8
- In mixed form: 13/8
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