Subtract 80/42 from 21/24
1st number: 21/24, 2nd number: 1 38/42
21/24 - 80/42 is -173/168.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 24 and 42 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 24 × 7 = 168,
21/24 = 21 × 7/24 × 7 = 147/168 - Likewise, for the 2nd fraction, since 42 × 4 = 168,
80/42 = 80 × 4/42 × 4 = 320/168 - Subtract the two like fractions:
147/168 - 320/168 = 147 - 320/168 = -173/168
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