Subtract 2/21 from 4/45
4/45 - 2/21 is -2/315.
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,
4/45 = 4 × 7/45 × 7 = 28/315 - Likewise, for the 2nd fraction, since 21 × 15 = 315,
2/21 = 2 × 15/21 × 15 = 30/315 - Subtract the two like fractions:
28/315 - 30/315 = 28 - 30/315 = -2/315
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