Subtract 21/7 from 18/4
1st number: 4 2/4, 2nd number: 3 0/7
18/4 - 21/7 is 3/2.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 7 is 28
Next, find the equivalent fraction of both fractional numbers with denominator 28 - For the 1st fraction, since 4 × 7 = 28,
18/4 = 18 × 7/4 × 7 = 126/28 - Likewise, for the 2nd fraction, since 7 × 4 = 28,
21/7 = 21 × 4/7 × 4 = 84/28 - Subtract the two like fractions:
126/28 - 84/28 = 126 - 84/28 = 42/28 - After reducing the fraction, the answer is 3/2
- In mixed form: 11/2
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