Subtract 25/45 from 20/42
20/42 - 25/45 is -5/63.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 45 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 42 × 15 = 630,
20/42 = 20 × 15/42 × 15 = 300/630 - Likewise, for the 2nd fraction, since 45 × 14 = 630,
25/45 = 25 × 14/45 × 14 = 350/630 - Subtract the two like fractions:
300/630 - 350/630 = 300 - 350/630 = -50/630 - After reducing the fraction, the answer is -5/63
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