Subtract 20/42 from 7/16
7/16 - 20/42 is -13/336.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 16 and 42 is 336
Next, find the equivalent fraction of both fractional numbers with denominator 336 - For the 1st fraction, since 16 × 21 = 336,
7/16 = 7 × 21/16 × 21 = 147/336 - Likewise, for the 2nd fraction, since 42 × 8 = 336,
20/42 = 20 × 8/42 × 8 = 160/336 - Subtract the two like fractions:
147/336 - 160/336 = 147 - 160/336 = -13/336
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