Subtract 81/49 from 90/70
1st number: 1 20/70, 2nd number: 1 32/49
90/70 - 81/49 is -18/49.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 49 is 490
Next, find the equivalent fraction of both fractional numbers with denominator 490 - For the 1st fraction, since 70 × 7 = 490,
90/70 = 90 × 7/70 × 7 = 630/490 - Likewise, for the 2nd fraction, since 49 × 10 = 490,
81/49 = 81 × 10/49 × 10 = 810/490 - Subtract the two like fractions:
630/490 - 810/490 = 630 - 810/490 = -180/490 - After reducing the fraction, the answer is -18/49
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