Subtract 72/70 from 84/90
1st number: 84/90, 2nd number: 1 2/70
84/90 - 72/70 is -2/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 70 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 90 × 7 = 630,
84/90 = 84 × 7/90 × 7 = 588/630 - Likewise, for the 2nd fraction, since 70 × 9 = 630,
72/70 = 72 × 9/70 × 9 = 648/630 - Subtract the two like fractions:
588/630 - 648/630 = 588 - 648/630 = -60/630 - After reducing the fraction, the answer is -2/21
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