Subtract 21/70 from 15/63
15/63 - 21/70 is -13/210.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 63 and 70 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 63 × 10 = 630,
15/63 = 15 × 10/63 × 10 = 150/630 - Likewise, for the 2nd fraction, since 70 × 9 = 630,
21/70 = 21 × 9/70 × 9 = 189/630 - Subtract the two like fractions:
150/630 - 189/630 = 150 - 189/630 = -39/630 - After reducing the fraction, the answer is -13/210
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