Subtract 21/30 from 1/21
1/21 - 21/30 is -137/210.
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,
1/21 = 1 × 10/21 × 10 = 10/210 - Likewise, for the 2nd fraction, since 30 × 7 = 210,
21/30 = 21 × 7/30 × 7 = 147/210 - Subtract the two like fractions:
10/210 - 147/210 = 10 - 147/210 = -137/210
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