Subtract 15/30 from 2/21
2/21 - 15/30 is -17/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 30 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 21 × 10 = 210,
2/21 = 2 × 10/21 × 10 = 20/210 - Likewise, for the 2nd fraction, since 30 × 7 = 210,
15/30 = 15 × 7/30 × 7 = 105/210 - Subtract the two like fractions:
20/210 - 105/210 = 20 - 105/210 = -85/210 - After reducing the fraction, the answer is -17/42
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