Subtract 21/70 from 42/12
1st number: 3 6/12, 2nd number: 21/70
42/12 - 21/70 is 16/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 70 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 12 × 35 = 420,
42/12 = 42 × 35/12 × 35 = 1470/420 - Likewise, for the 2nd fraction, since 70 × 6 = 420,
21/70 = 21 × 6/70 × 6 = 126/420 - Subtract the two like fractions:
1470/420 - 126/420 = 1470 - 126/420 = 1344/420 - After reducing the fraction, the answer is 16/5
- In mixed form: 31/5
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