Subtract 84/80 from 30/42
1st number: 30/42, 2nd number: 1 4/80
30/42 - 84/80 is -47/140.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 80 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 42 × 40 = 1680,
30/42 = 30 × 40/42 × 40 = 1200/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
84/80 = 84 × 21/80 × 21 = 1764/1680 - Subtract the two like fractions:
1200/1680 - 1764/1680 = 1200 - 1764/1680 = -564/1680 - After reducing the fraction, the answer is -47/140
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