Subtract 4/72 from 28/21
1st number: 1 7/21, 2nd number: 4/72
28/21 - 4/72 is 23/18.
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,
28/21 = 28 × 24/21 × 24 = 672/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
4/72 = 4 × 7/72 × 7 = 28/504 - Subtract the two like fractions:
672/504 - 28/504 = 672 - 28/504 = 644/504 - After reducing the fraction, the answer is 23/18
- In mixed form: 15/18
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