Subtract 72/21 from 30/3
1st number: 10 0/3, 2nd number: 3 9/21
30/3 - 72/21 is 46/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 3 and 21 is 21
Next, find the equivalent fraction of both fractional numbers with denominator 21 - For the 1st fraction, since 3 × 7 = 21,
30/3 = 30 × 7/3 × 7 = 210/21 - Likewise, for the 2nd fraction, since 21 × 1 = 21,
72/21 = 72 × 1/21 × 1 = 72/21 - Subtract the two like fractions:
210/21 - 72/21 = 210 - 72/21 = 138/21 - After reducing the fraction, the answer is 46/7
- In mixed form: 64/7
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