Subtract 40/21 from 30/20
1st number: 1 10/20, 2nd number: 1 19/21
30/20 - 40/21 is -17/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 21 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
30/20 = 30 × 21/20 × 21 = 630/420 - Likewise, for the 2nd fraction, since 21 × 20 = 420,
40/21 = 40 × 20/21 × 20 = 800/420 - Subtract the two like fractions:
630/420 - 800/420 = 630 - 800/420 = -170/420 - After reducing the fraction, the answer is -17/42
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