Subtract 15/8 from 30/70
1st number: 30/70, 2nd number: 1 7/8
30/70 - 15/8 is -81/56.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 8 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 70 × 4 = 280,
30/70 = 30 × 4/70 × 4 = 120/280 - Likewise, for the 2nd fraction, since 8 × 35 = 280,
15/8 = 15 × 35/8 × 35 = 525/280 - Subtract the two like fractions:
120/280 - 525/280 = 120 - 525/280 = -405/280 - After reducing the fraction, the answer is -81/56
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