Subtract 21/9 from 40/7
1st number: 5 5/7, 2nd number: 2 3/9
40/7 - 21/9 is 71/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 9 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 7 × 9 = 63,
40/7 = 40 × 9/7 × 9 = 360/63 - Likewise, for the 2nd fraction, since 9 × 7 = 63,
21/9 = 21 × 7/9 × 7 = 147/63 - Subtract the two like fractions:
360/63 - 147/63 = 360 - 147/63 = 213/63 - After reducing the fraction, the answer is 71/21
- In mixed form: 38/21
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