Add 1/21 and 72/15
1st number: 1/21, 2nd number: 4 12/15
1/21 + 72/15 is 509/105.
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,
1/21 = 1 × 5/21 × 5 = 5/105 - Likewise, for the 2nd fraction, since 15 × 7 = 105,
72/15 = 72 × 7/15 × 7 = 504/105 - Add the two like fractions:
5/105 + 504/105 = 5 + 504/105 = 509/105 - So, 1/21 + 72/15 = 509/105
In mixed form: 489/105
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