Subtract 30/40 from 21/35
21/35 - 30/40 is -3/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 35 and 40 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 35 × 8 = 280,
21/35 = 21 × 8/35 × 8 = 168/280 - Likewise, for the 2nd fraction, since 40 × 7 = 280,
30/40 = 30 × 7/40 × 7 = 210/280 - Subtract the two like fractions:
168/280 - 210/280 = 168 - 210/280 = -42/280 - After reducing the fraction, the answer is -3/20
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