Subtract 4/42 from 3/20
3/20 - 4/42 is 23/420.
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,
3/20 = 3 × 21/20 × 21 = 63/420 - Likewise, for the 2nd fraction, since 42 × 10 = 420,
4/42 = 4 × 10/42 × 10 = 40/420 - Subtract the two like fractions:
63/420 - 40/420 = 63 - 40/420 = 23/420
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