Subtract 42/21 from 35/45
1st number: 35/45, 2nd number: 2 0/21
35/45 - 42/21 is -11/9.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 21 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 45 × 7 = 315,
35/45 = 35 × 7/45 × 7 = 245/315 - Likewise, for the 2nd fraction, since 21 × 15 = 315,
42/21 = 42 × 15/21 × 15 = 630/315 - Subtract the two like fractions:
245/315 - 630/315 = 245 - 630/315 = -385/315 - After reducing the fraction, the answer is -11/9
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