Subtract 21/18 from 45/7
1st number: 6 3/7, 2nd number: 1 3/18
45/7 - 21/18 is 221/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 18 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 7 × 18 = 126,
45/7 = 45 × 18/7 × 18 = 810/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
21/18 = 21 × 7/18 × 7 = 147/126 - Subtract the two like fractions:
810/126 - 147/126 = 810 - 147/126 = 663/126 - After reducing the fraction, the answer is 221/42
- In mixed form: 511/42
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