Subtract 72/80 from 20/70
20/70 - 72/80 is -43/70.
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,
20/70 = 20 × 8/70 × 8 = 160/560 - Likewise, for the 2nd fraction, since 80 × 7 = 560,
72/80 = 72 × 7/80 × 7 = 504/560 - Subtract the two like fractions:
160/560 - 504/560 = 160 - 504/560 = -344/560 - After reducing the fraction, the answer is -43/70
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