Subtract 20/90 from 42/63
42/63 - 20/90 is 4/9.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 63 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 63 × 10 = 630,
42/63 = 42 × 10/63 × 10 = 420/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
20/90 = 20 × 7/90 × 7 = 140/630 - Subtract the two like fractions:
420/630 - 140/630 = 420 - 140/630 = 280/630 - After reducing the fraction, the answer is 4/9
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