Subtract 20/63 from 42/90
42/90 - 20/63 is 47/315.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 63 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 90 × 7 = 630,
42/90 = 42 × 7/90 × 7 = 294/630 - Likewise, for the 2nd fraction, since 63 × 10 = 630,
20/63 = 20 × 10/63 × 10 = 200/630 - Subtract the two like fractions:
294/630 - 200/630 = 294 - 200/630 = 94/630 - After reducing the fraction, the answer is 47/315
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