Subtract 21/45 from 3/7
3/7 - 21/45 is -4/105.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 45 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 7 × 45 = 315,
3/7 = 3 × 45/7 × 45 = 135/315 - Likewise, for the 2nd fraction, since 45 × 7 = 315,
21/45 = 21 × 7/45 × 7 = 147/315 - Subtract the two like fractions:
135/315 - 147/315 = 135 - 147/315 = -12/315 - After reducing the fraction, the answer is -4/105
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