Subtract 30/6 from 72/21
1st number: 3 9/21, 2nd number: 5 0/6
72/21 - 30/6 is -11/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 6 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 21 × 2 = 42,
72/21 = 72 × 2/21 × 2 = 144/42 - Likewise, for the 2nd fraction, since 6 × 7 = 42,
30/6 = 30 × 7/6 × 7 = 210/42 - Subtract the two like fractions:
144/42 - 210/42 = 144 - 210/42 = -66/42 - After reducing the fraction, the answer is -11/7
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