Subtract 30/72 from 9/42
9/42 - 30/72 is -17/84.
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,
9/42 = 9 × 12/42 × 12 = 108/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
30/72 = 30 × 7/72 × 7 = 210/504 - Subtract the two like fractions:
108/504 - 210/504 = 108 - 210/504 = -102/504 - After reducing the fraction, the answer is -17/84
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