Subtract 18/9 from 30/21
1st number: 1 9/21, 2nd number: 2 0/9
30/21 - 18/9 is -4/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 9 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 21 × 3 = 63,
30/21 = 30 × 3/21 × 3 = 90/63 - Likewise, for the 2nd fraction, since 9 × 7 = 63,
18/9 = 18 × 7/9 × 7 = 126/63 - Subtract the two like fractions:
90/63 - 126/63 = 90 - 126/63 = -36/63 - After reducing the fraction, the answer is -4/7
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