Subtract 30/10 from 21/27
1st number: 21/27, 2nd number: 3 0/10
21/27 - 30/10 is -20/9.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 27 and 10 is 270
Next, find the equivalent fraction of both fractional numbers with denominator 270 - For the 1st fraction, since 27 × 10 = 270,
21/27 = 21 × 10/27 × 10 = 210/270 - Likewise, for the 2nd fraction, since 10 × 27 = 270,
30/10 = 30 × 27/10 × 27 = 810/270 - Subtract the two like fractions:
210/270 - 810/270 = 210 - 810/270 = -600/270 - After reducing the fraction, the answer is -20/9
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