Subtract 45/42 from 21/6
1st number: 3 3/6, 2nd number: 1 3/42
21/6 - 45/42 is 17/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 6 and 42 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 6 × 7 = 42,
21/6 = 21 × 7/6 × 7 = 147/42 - Likewise, for the 2nd fraction, since 42 × 1 = 42,
45/42 = 45 × 1/42 × 1 = 45/42 - Subtract the two like fractions:
147/42 - 45/42 = 147 - 45/42 = 102/42 - After reducing the fraction, the answer is 17/7
- In mixed form: 23/7
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