Subtract 9/20 from 4/21
421 - 920 is -109420.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 21 × 20 = 420,
421 = 4 × 2021 × 20 = 80420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
920 = 9 × 2120 × 21 = 189420 - Subtract the two like fractions:
80420 - 189420 = 80 - 189420 = -109420
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