Subtract 15/21 from 10/45
10/45 - 15/21 is -31/63.
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,
10/45 = 10 × 7/45 × 7 = 70/315 - Likewise, for the 2nd fraction, since 21 × 15 = 315,
15/21 = 15 × 15/21 × 15 = 225/315 - Subtract the two like fractions:
70/315 - 225/315 = 70 - 225/315 = -155/315 - After reducing the fraction, the answer is -31/63
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