Subtract 42/9 from 20/5
1st number: 4 0/5, 2nd number: 4 6/9
20/5 - 42/9 is -2/3.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 9 is 45
Next, find the equivalent fraction of both fractional numbers with denominator 45 - For the 1st fraction, since 5 × 9 = 45,
20/5 = 20 × 9/5 × 9 = 180/45 - Likewise, for the 2nd fraction, since 9 × 5 = 45,
42/9 = 42 × 5/9 × 5 = 210/45 - Subtract the two like fractions:
180/45 - 210/45 = 180 - 210/45 = -30/45 - After reducing the fraction, the answer is -2/3
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