Subtract 63/21 from 30/70
1st number: 30/70, 2nd number: 3 0/21
30/70 - 63/21 is -18/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 21 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 70 × 3 = 210,
30/70 = 30 × 3/70 × 3 = 90/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
63/21 = 63 × 10/21 × 10 = 630/210 - Subtract the two like fractions:
90/210 - 630/210 = 90 - 630/210 = -540/210 - After reducing the fraction, the answer is -18/7
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