Subtract 9/72 from 21/7
1st number: 3 0/7, 2nd number: 9/72
21/7 - 9/72 is 23/8.
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,
9/72 = 9 × 7/72 × 7 = 63/504 - Subtract the two like fractions:
1512/504 - 63/504 = 1512 - 63/504 = 1449/504 - After reducing the fraction, the answer is 23/8
- In mixed form: 27/8
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