Subtract 42/70 from 20/50
20/50 - 42/70 is -1/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 50 and 70 is 350
Next, find the equivalent fraction of both fractional numbers with denominator 350 - For the 1st fraction, since 50 × 7 = 350,
20/50 = 20 × 7/50 × 7 = 140/350 - Likewise, for the 2nd fraction, since 70 × 5 = 350,
42/70 = 42 × 5/70 × 5 = 210/350 - Subtract the two like fractions:
140/350 - 210/350 = 140 - 210/350 = -70/350 - After reducing the fraction, the answer is -1/5
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