Subtract 21/45 from 15/21
15/21 - 21/45 is 26/105.
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,
15/21 = 15 × 15/21 × 15 = 225/315 - Likewise, for the 2nd fraction, since 45 × 7 = 315,
21/45 = 21 × 7/45 × 7 = 147/315 - Subtract the two like fractions:
225/315 - 147/315 = 225 - 147/315 = 78/315 - After reducing the fraction, the answer is 26/105
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