Subtract 15/35 from 3/21
3/21 - 15/35 is -2/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 35 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 21 × 5 = 105,
3/21 = 3 × 5/21 × 5 = 15/105 - Likewise, for the 2nd fraction, since 35 × 3 = 105,
15/35 = 15 × 3/35 × 3 = 45/105 - Subtract the two like fractions:
15/105 - 45/105 = 15 - 45/105 = -30/105 - After reducing the fraction, the answer is -2/7
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