Subtract 21/30 from 28/21
1st number: 1 7/21, 2nd number: 21/30
28/21 - 21/30 is 19/30.
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,
28/21 = 28 × 10/21 × 10 = 280/210 - Likewise, for the 2nd fraction, since 30 × 7 = 210,
21/30 = 21 × 7/30 × 7 = 147/210 - Subtract the two like fractions:
280/210 - 147/210 = 280 - 147/210 = 133/210 - After reducing the fraction, the answer is 19/30
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