Subtract 21/12 from 40/70
1st number: 40/70, 2nd number: 1 9/12
40/70 - 21/12 is -33/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 12 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 70 × 6 = 420,
40/70 = 40 × 6/70 × 6 = 240/420 - Likewise, for the 2nd fraction, since 12 × 35 = 420,
21/12 = 21 × 35/12 × 35 = 735/420 - Subtract the two like fractions:
240/420 - 735/420 = 240 - 735/420 = -495/420 - After reducing the fraction, the answer is -33/28
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