Subtract 90/70 from 70/84
1st number: 70/84, 2nd number: 1 20/70
70/84 - 90/70 is -19/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 70 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 84 × 5 = 420,
70/84 = 70 × 5/84 × 5 = 350/420 - Likewise, for the 2nd fraction, since 70 × 6 = 420,
90/70 = 90 × 6/70 × 6 = 540/420 - Subtract the two like fractions:
350/420 - 540/420 = 350 - 540/420 = -190/420 - After reducing the fraction, the answer is -19/42
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