Add 72/21 and 15/72, Solve 3 9/21 + 15/72 as a fraction

Add 72/21 and 15/72

1^st number: 3 9/21, 2^nd number: 15/72

72/21 + 15/72 is 611/168.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 72 is 504

Next, find the equivalent fraction of both fractional numbers with denominator 504
For the 1st fraction, since 21 × 24 = 504,
72/21 = 72 × 24/21 × 24 = 1728/504
Likewise, for the 2nd fraction, since 72 × 7 = 504,
15/72 = 15 × 7/72 × 7 = 105/504
Add the two like fractions:
1728/504 + 105/504 = 1728 + 105/504 = 1833/504
1833/504 simplified gives 611/168
So, 72/21 + 15/72 = 611/168
In mixed form: 3107/168

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