Subtract 20/42 from 9/24
9/24 - 20/42 is -17/168.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 24 and 42 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 24 × 7 = 168,
9/24 = 9 × 7/24 × 7 = 63/168 - Likewise, for the 2nd fraction, since 42 × 4 = 168,
20/42 = 20 × 4/42 × 4 = 80/168 - Subtract the two like fractions:
63/168 - 80/168 = 63 - 80/168 = -17/168
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