Add 72/15 and 20/21
1st number: 4 12/15, 2nd number: 20/21
72/15 + 20/21 is 604/105.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 15 × 7 = 105,
72/15 = 72 × 7/15 × 7 = 504/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
20/21 = 20 × 5/21 × 5 = 100/105 - Add the two like fractions:
504/105 + 100/105 = 504 + 100/105 = 604/105 - So, 72/15 + 20/21 = 604/105
In mixed form: 579/105
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