Subtract 42/72 from 10/21
10/21 - 42/72 is -3/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 21 × 24 = 504,
10/21 = 10 × 24/21 × 24 = 240/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
42/72 = 42 × 7/72 × 7 = 294/504 - Subtract the two like fractions:
240/504 - 294/504 = 240 - 294/504 = -54/504 - After reducing the fraction, the answer is -3/28
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