Subtract 5/45 from 18/21
18/21 - 5/45 is 47/63.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 45 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 21 × 15 = 315,
18/21 = 18 × 15/21 × 15 = 270/315 - Likewise, for the 2nd fraction, since 45 × 7 = 315,
5/45 = 5 × 7/45 × 7 = 35/315 - Subtract the two like fractions:
270/315 - 35/315 = 270 - 35/315 = 235/315 - After reducing the fraction, the answer is 47/63
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