Subtract 90/42 from 30/21
1st number: 1 9/21, 2nd number: 2 6/42
30/21 - 90/42 is -5/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 42 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 21 × 2 = 42,
30/21 = 30 × 2/21 × 2 = 60/42 - Likewise, for the 2nd fraction, since 42 × 1 = 42,
90/42 = 90 × 1/42 × 1 = 90/42 - Subtract the two like fractions:
60/42 - 90/42 = 60 - 90/42 = -30/42 - After reducing the fraction, the answer is -5/7
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