Subtract 3/20 from 45/42
1st number: 1 3/42, 2nd number: 3/20
45/42 - 3/20 is 129/140.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 42 × 10 = 420,
45/42 = 45 × 10/42 × 10 = 450/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
3/20 = 3 × 21/20 × 21 = 63/420 - Subtract the two like fractions:
450/420 - 63/420 = 450 - 63/420 = 387/420 - After reducing the fraction, the answer is 129/140
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