Subtract 21/80 from 42/12
1st number: 3 6/12, 2nd number: 21/80
42/12 - 21/80 is 259/80.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 80 is 240
Next, find the equivalent fraction of both fractional numbers with denominator 240 - For the 1st fraction, since 12 × 20 = 240,
42/12 = 42 × 20/12 × 20 = 840/240 - Likewise, for the 2nd fraction, since 80 × 3 = 240,
21/80 = 21 × 3/80 × 3 = 63/240 - Subtract the two like fractions:
840/240 - 63/240 = 840 - 63/240 = 777/240 - After reducing the fraction, the answer is 259/80
- In mixed form: 319/80
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