Subtract 28/18 from 21/8
1st number: 2 5/8, 2nd number: 1 10/18
21/8 - 28/18 is 77/72.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 18 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 8 × 9 = 72,
21/8 = 21 × 9/8 × 9 = 189/72 - Likewise, for the 2nd fraction, since 18 × 4 = 72,
28/18 = 28 × 4/18 × 4 = 112/72 - Subtract the two like fractions:
189/72 - 112/72 = 189 - 112/72 = 77/72 - In mixed form: 15/72
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