Subtract 18/72 from 42/84
42/84 - 18/72 is 1/4.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 84 × 6 = 504,
42/84 = 42 × 6/84 × 6 = 252/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
18/72 = 18 × 7/72 × 7 = 126/504 - Subtract the two like fractions:
252/504 - 126/504 = 252 - 126/504 = 126/504 - After reducing the fraction, the answer is 1/4
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