Subtract 20/80 from 4/70
4/70 - 20/80 is -27/140.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 80 is 560
Next, find the equivalent fraction of both fractional numbers with denominator 560 - For the 1st fraction, since 70 × 8 = 560,
4/70 = 4 × 8/70 × 8 = 32/560 - Likewise, for the 2nd fraction, since 80 × 7 = 560,
20/80 = 20 × 7/80 × 7 = 140/560 - Subtract the two like fractions:
32/560 - 140/560 = 32 - 140/560 = -108/560 - After reducing the fraction, the answer is -27/140
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