Subtract 21/12 from 30/35
1st number: 30/35, 2nd number: 1 9/12
30/35 - 21/12 is -25/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 35 and 12 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 35 × 12 = 420,
30/35 = 30 × 12/35 × 12 = 360/420 - Likewise, for the 2nd fraction, since 12 × 35 = 420,
21/12 = 21 × 35/12 × 35 = 735/420 - Subtract the two like fractions:
360/420 - 735/420 = 360 - 735/420 = -375/420 - After reducing the fraction, the answer is -25/28
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