Subtract 1/42 from 20/90
20/90 - 1/42 is 25/126.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 42 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 90 × 7 = 630,
20/90 = 20 × 7/90 × 7 = 140/630 - Likewise, for the 2nd fraction, since 42 × 15 = 630,
1/42 = 1 × 15/42 × 15 = 15/630 - Subtract the two like fractions:
140/630 - 15/630 = 140 - 15/630 = 125/630 - After reducing the fraction, the answer is 25/126
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