Subtract 20/18 from 42/70
1st number: 42/70, 2nd number: 1 2/18
42/70 - 20/18 is -23/45.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 18 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 70 × 9 = 630,
42/70 = 42 × 9/70 × 9 = 378/630 - Likewise, for the 2nd fraction, since 18 × 35 = 630,
20/18 = 20 × 35/18 × 35 = 700/630 - Subtract the two like fractions:
378/630 - 700/630 = 378 - 700/630 = -322/630 - After reducing the fraction, the answer is -23/45
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