Subtract 80/42 from 90/18
1st number: 5 0/18, 2nd number: 1 38/42
90/18 - 80/42 is 65/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 42 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 18 × 7 = 126,
90/18 = 90 × 7/18 × 7 = 630/126 - Likewise, for the 2nd fraction, since 42 × 3 = 126,
80/42 = 80 × 3/42 × 3 = 240/126 - Subtract the two like fractions:
630/126 - 240/126 = 630 - 240/126 = 390/126 - After reducing the fraction, the answer is 65/21
- In mixed form: 32/21
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