Subtract 9/20 from 30/70
30/70 - 9/20 is -3/140.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 20 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 70 × 2 = 140,
30/70 = 30 × 2/70 × 2 = 60/140 - Likewise, for the 2nd fraction, since 20 × 7 = 140,
9/20 = 9 × 7/20 × 7 = 63/140 - Subtract the two like fractions:
60/140 - 63/140 = 60 - 63/140 = -3/140
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