Subtract 28/72 from 21/7
1st number: 3 0/7, 2nd number: 28/72
21/7 - 28/72 is 47/18.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 7 × 72 = 504,
21/7 = 21 × 72/7 × 72 = 1512/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
28/72 = 28 × 7/72 × 7 = 196/504 - Subtract the two like fractions:
1512/504 - 196/504 = 1512 - 196/504 = 1316/504 - After reducing the fraction, the answer is 47/18
- In mixed form: 211/18
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