Subtract 20/70 from 45/80
45/80 - 20/70 is 31/112.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 70 is 560
Next, find the equivalent fraction of both fractional numbers with denominator 560 - For the 1st fraction, since 80 × 7 = 560,
45/80 = 45 × 7/80 × 7 = 315/560 - Likewise, for the 2nd fraction, since 70 × 8 = 560,
20/70 = 20 × 8/70 × 8 = 160/560 - Subtract the two like fractions:
315/560 - 160/560 = 315 - 160/560 = 155/560 - After reducing the fraction, the answer is 31/112
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