Subtract 42/27 from 90/70
1st number: 1 20/70, 2nd number: 1 15/27
90/70 - 42/27 is -17/63.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 27 is 1890
Next, find the equivalent fraction of both fractional numbers with denominator 1890 - For the 1st fraction, since 70 × 27 = 1890,
90/70 = 90 × 27/70 × 27 = 2430/1890 - Likewise, for the 2nd fraction, since 27 × 70 = 1890,
42/27 = 42 × 70/27 × 70 = 2940/1890 - Subtract the two like fractions:
2430/1890 - 2940/1890 = 2430 - 2940/1890 = -510/1890 - After reducing the fraction, the answer is -17/63
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