Subtract 21/7 from 21/4
1st number: 5 1/4, 2nd number: 3 0/7
21/4 - 21/7 is 9/4.
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,
21/4 = 21 × 7/4 × 7 = 147/28 - Likewise, for the 2nd fraction, since 7 × 4 = 28,
21/7 = 21 × 4/7 × 4 = 84/28 - Subtract the two like fractions:
147/28 - 84/28 = 147 - 84/28 = 63/28 - After reducing the fraction, the answer is 9/4
- In mixed form: 21/4
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