Subtract 20/42 from 15/8
1st number: 1 7/8, 2nd number: 20/42
15/8 - 20/42 is 235/168.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 42 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 8 × 21 = 168,
15/8 = 15 × 21/8 × 21 = 315/168 - Likewise, for the 2nd fraction, since 42 × 4 = 168,
20/42 = 20 × 4/42 × 4 = 80/168 - Subtract the two like fractions:
315/168 - 80/168 = 315 - 80/168 = 235/168 - In mixed form: 167/168
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