Add 28/21 and 7/72, Solve 1 7/21 + 7/72 as a fraction

Add 28/21 and 7/72

1^st number: 1 7/21, 2^nd number: 7/72

28/21 + 7/72 is 103/72.

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,
28/21 = 28 × 24/21 × 24 = 672/504
Likewise, for the 2nd fraction, since 72 × 7 = 504,
7/72 = 7 × 7/72 × 7 = 49/504
Add the two like fractions:
672/504 + 49/504 = 672 + 49/504 = 721/504
721/504 simplified gives 103/72
So, 28/21 + 7/72 = 103/72
In mixed form: 131/72

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