Add 28/21 and 25/72, Solve 1 7/21 + 25/72 as a fraction

Add 28/21 and 25/72

1^st number: 1 7/21, 2^nd number: 25/72

28/21 + 25/72 is 121/72.

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,
25/72 = 25 × 7/72 × 7 = 175/504
Add the two like fractions:
672/504 + 175/504 = 672 + 175/504 = 847/504
847/504 simplified gives 121/72
So, 28/21 + 25/72 = 121/72
In mixed form: 149/72

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