Subtract 30/80 from 21/40
21/40 - 30/80 is 3/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 80 is 80
Next, find the equivalent fraction of both fractional numbers with denominator 80 - For the 1st fraction, since 40 × 2 = 80,
21/40 = 21 × 2/40 × 2 = 42/80 - Likewise, for the 2nd fraction, since 80 × 1 = 80,
30/80 = 30 × 1/80 × 1 = 30/80 - Subtract the two like fractions:
42/80 - 30/80 = 42 - 30/80 = 12/80 - After reducing the fraction, the answer is 3/20
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