Add 72/21 and 10/15
1st number: 3 9/21, 2nd number: 10/15
72/21 + 10/15 is 86/21.
Steps for adding 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,
10/15 = 10 × 7/15 × 7 = 70/105 - Add the two like fractions:
360/105 + 70/105 = 360 + 70/105 = 430/105 - 430/105 simplified gives 86/21
- So, 72/21 + 10/15 = 86/21
In mixed form: 42/21
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