Subtract 42/63 from 45/72
45/72 - 42/63 is -1/24.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 63 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 72 × 7 = 504,
45/72 = 45 × 7/72 × 7 = 315/504 - Likewise, for the 2nd fraction, since 63 × 8 = 504,
42/63 = 42 × 8/63 × 8 = 336/504 - Subtract the two like fractions:
315/504 - 336/504 = 315 - 336/504 = -21/504 - After reducing the fraction, the answer is -1/24
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