Subtract 42/15 from 9/21
1st number: 9/21, 2nd number: 2 12/15
9/21 - 42/15 is -83/35.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 15 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 21 × 5 = 105,
9/21 = 9 × 5/21 × 5 = 45/105 - Likewise, for the 2nd fraction, since 15 × 7 = 105,
42/15 = 42 × 7/15 × 7 = 294/105 - Subtract the two like fractions:
45/105 - 294/105 = 45 - 294/105 = -249/105 - After reducing the fraction, the answer is -83/35
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