Subtract 15/72 from 30/42
30/42 - 15/72 is 85/168.
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,
30/42 = 30 × 12/42 × 12 = 360/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
15/72 = 15 × 7/72 × 7 = 105/504 - Subtract the two like fractions:
360/504 - 105/504 = 360 - 105/504 = 255/504 - After reducing the fraction, the answer is 85/168
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