Subtract 21/7 from 42/45
1st number: 42/45, 2nd number: 3 0/7
42/45 - 21/7 is -31/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 7 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 45 × 7 = 315,
42/45 = 42 × 7/45 × 7 = 294/315 - Likewise, for the 2nd fraction, since 7 × 45 = 315,
21/7 = 21 × 45/7 × 45 = 945/315 - Subtract the two like fractions:
294/315 - 945/315 = 294 - 945/315 = -651/315 - After reducing the fraction, the answer is -31/15
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