Subtract 90/30 from 21/49
1st number: 21/49, 2nd number: 3 0/30
21/49 - 90/30 is -18/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 49 and 30 is 1470
Next, find the equivalent fraction of both fractional numbers with denominator 1470 - For the 1st fraction, since 49 × 30 = 1470,
21/49 = 21 × 30/49 × 30 = 630/1470 - Likewise, for the 2nd fraction, since 30 × 49 = 1470,
90/30 = 90 × 49/30 × 49 = 4410/1470 - Subtract the two like fractions:
630/1470 - 4410/1470 = 630 - 4410/1470 = -3780/1470 - After reducing the fraction, the answer is -18/7
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