Subtract 21/18 from 72/70
1st number: 1 2/70, 2nd number: 1 3/18
72/70 - 21/18 is -29/210.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 18 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 70 × 9 = 630,
72/70 = 72 × 9/70 × 9 = 648/630 - Likewise, for the 2nd fraction, since 18 × 35 = 630,
21/18 = 21 × 35/18 × 35 = 735/630 - Subtract the two like fractions:
648/630 - 735/630 = 648 - 735/630 = -87/630 - After reducing the fraction, the answer is -29/210
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