Subtract 30/42 from 21/20
1st number: 1 1/20, 2nd number: 30/42
21/20 - 30/42 is 47/140.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 42 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
21/20 = 21 × 21/20 × 21 = 441/420 - Likewise, for the 2nd fraction, since 42 × 10 = 420,
30/42 = 30 × 10/42 × 10 = 300/420 - Subtract the two like fractions:
441/420 - 300/420 = 441 - 300/420 = 141/420 - After reducing the fraction, the answer is 47/140
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