Subtract 42/30 from 28/80
1st number: 28/80, 2nd number: 1 12/30
28/80 - 42/30 is -21/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 30 is 240
Next, find the equivalent fraction of both fractional numbers with denominator 240 - For the 1st fraction, since 80 × 3 = 240,
28/80 = 28 × 3/80 × 3 = 84/240 - Likewise, for the 2nd fraction, since 30 × 8 = 240,
42/30 = 42 × 8/30 × 8 = 336/240 - Subtract the two like fractions:
84/240 - 336/240 = 84 - 336/240 = -252/240 - After reducing the fraction, the answer is -21/20
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