Subtract 30/70 from 21/50
21/50 - 30/70 is -3/350.
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,
21/50 = 21 × 7/50 × 7 = 147/350 - Likewise, for the 2nd fraction, since 70 × 5 = 350,
30/70 = 30 × 5/70 × 5 = 150/350 - Subtract the two like fractions:
147/350 - 150/350 = 147 - 150/350 = -3/350
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