Subtract 4/7 from 20/45
20/45 - 4/7 is -8/63.
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,
20/45 = 20 × 7/45 × 7 = 140/315 - Likewise, for the 2nd fraction, since 7 × 45 = 315,
4/7 = 4 × 45/7 × 45 = 180/315 - Subtract the two like fractions:
140/315 - 180/315 = 140 - 180/315 = -40/315 - After reducing the fraction, the answer is -8/63
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