Subtract 1/15 from 72/21
1st number: 3 9/21, 2nd number: 1/15
72/21 - 1/15 is 353/105.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 15 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 15 × 7 = 105,
1/15 = 1 × 7/15 × 7 = 7/105 - Subtract the two like fractions:
360/105 - 7/105 = 360 - 7/105 = 353/105 - In mixed form: 338/105
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