Subtract 1/21 from 15/45
15/45 - 1/21 is 2/7.
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,
15/45 = 15 × 7/45 × 7 = 105/315 - Likewise, for the 2nd fraction, since 21 × 15 = 315,
1/21 = 1 × 15/21 × 15 = 15/315 - Subtract the two like fractions:
105/315 - 15/315 = 105 - 15/315 = 90/315 - After reducing the fraction, the answer is 2/7
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