Subtract 3/72 from 12/21
12/21 - 3/72 is 89/168.
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,
12/21 = 12 × 24/21 × 24 = 288/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
3/72 = 3 × 7/72 × 7 = 21/504 - Subtract the two like fractions:
288/504 - 21/504 = 288 - 21/504 = 267/504 - After reducing the fraction, the answer is 89/168
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