Subtract 15/7 from 72/21
1st number: 3 9/21, 2nd number: 2 1/7
72/21 - 15/7 is 9/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 7 is 21
Next, find the equivalent fraction of both fractional numbers with denominator 21 - For the 1st fraction, since 21 × 1 = 21,
72/21 = 72 × 1/21 × 1 = 72/21 - Likewise, for the 2nd fraction, since 7 × 3 = 21,
15/7 = 15 × 3/7 × 3 = 45/21 - Subtract the two like fractions:
72/21 - 45/21 = 72 - 45/21 = 27/21 - After reducing the fraction, the answer is 9/7
- In mixed form: 12/7
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