Subtract 72/80 from 30/84
30/84 - 72/80 is -19/35.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 80 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 84 × 20 = 1680,
30/84 = 30 × 20/84 × 20 = 600/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
72/80 = 72 × 21/80 × 21 = 1512/1680 - Subtract the two like fractions:
600/1680 - 1512/1680 = 600 - 1512/1680 = -912/1680 - After reducing the fraction, the answer is -19/35
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