Subtract 28/84 from 90/70
1st number: 1 20/70, 2nd number: 28/84
90/70 - 28/84 is 20/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 84 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 70 × 6 = 420,
90/70 = 90 × 6/70 × 6 = 540/420 - Likewise, for the 2nd fraction, since 84 × 5 = 420,
28/84 = 28 × 5/84 × 5 = 140/420 - Subtract the two like fractions:
540/420 - 140/420 = 540 - 140/420 = 400/420 - After reducing the fraction, the answer is 20/21
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