Subtract 12/72 from 20/42
20/42 - 12/72 is 13/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 42 × 12 = 504,
20/42 = 20 × 12/42 × 12 = 240/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
12/72 = 12 × 7/72 × 7 = 84/504 - Subtract the two like fractions:
240/504 - 84/504 = 240 - 84/504 = 156/504 - After reducing the fraction, the answer is 13/42
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