Subtract 12/70 from 21/63
21/63 - 12/70 is 17/105.
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,
21/63 = 21 × 10/63 × 10 = 210/630 - Likewise, for the 2nd fraction, since 70 × 9 = 630,
12/70 = 12 × 9/70 × 9 = 108/630 - Subtract the two like fractions:
210/630 - 108/630 = 210 - 108/630 = 102/630 - After reducing the fraction, the answer is 17/105
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