Subtract 10/5 from 72/21
1st number: 3 9/21, 2nd number: 2 0/5
72/21 - 10/5 is 10/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 5 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 21 × 5 = 105,
72/21 = 72 × 5/21 × 5 = 360/105 - Likewise, for the 2nd fraction, since 5 × 21 = 105,
10/5 = 10 × 21/5 × 21 = 210/105 - Subtract the two like fractions:
360/105 - 210/105 = 360 - 210/105 = 150/105 - After reducing the fraction, the answer is 10/7
- In mixed form: 13/7
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