Subtract 4/80 from 21/12
1st number: 1 9/12, 2nd number: 4/80
21/12 - 4/80 is 17/10.
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,
21/12 = 21 × 20/12 × 20 = 420/240 - Likewise, for the 2nd fraction, since 80 × 3 = 240,
4/80 = 4 × 3/80 × 3 = 12/240 - Subtract the two like fractions:
420/240 - 12/240 = 420 - 12/240 = 408/240 - After reducing the fraction, the answer is 17/10
- In mixed form: 17/10
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