Subtract 21/63 from 28/70
28/70 - 21/63 is 1/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 63 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 70 × 9 = 630,
28/70 = 28 × 9/70 × 9 = 252/630 - Likewise, for the 2nd fraction, since 63 × 10 = 630,
21/63 = 21 × 10/63 × 10 = 210/630 - Subtract the two like fractions:
252/630 - 210/630 = 252 - 210/630 = 42/630 - After reducing the fraction, the answer is 1/15
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