Add 72/21 and 21/15
1st number: 3 9/21, 2nd number: 1 6/15
72/21 + 21/15 is 169/35.
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,
21/15 = 21 × 7/15 × 7 = 147/105 - Add the two like fractions:
360/105 + 147/105 = 360 + 147/105 = 507/105 - 507/105 simplified gives 169/35
- So, 72/21 + 21/15 = 169/35
In mixed form: 429/35
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