Subtract 20/42 from 9/20
9/20 - 20/42 is -11/420.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 42 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
9/20 = 9 × 21/20 × 21 = 189/420 - Likewise, for the 2nd fraction, since 42 × 10 = 420,
20/42 = 20 × 10/42 × 10 = 200/420 - Subtract the two like fractions:
189/420 - 200/420 = 189 - 200/420 = -11/420
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