Subtract 90/70 from 8/84
1st number: 8/84, 2nd number: 1 20/70
8/84 - 90/70 is -25/21.
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,
8/84 = 8 × 5/84 × 5 = 40/420 - Likewise, for the 2nd fraction, since 70 × 6 = 420,
90/70 = 90 × 6/70 × 6 = 540/420 - Subtract the two like fractions:
40/420 - 540/420 = 40 - 540/420 = -500/420 - After reducing the fraction, the answer is -25/21
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