Add 12/7 and 21/72, Solve 1 5/7 + 21/72 as a fraction

Add 12/7 and 21/72

1^st number: 1 5/7, 2^nd number: 21/72

12/7 + 21/72 is 337/168.

Find the least common denominator or LCM of the two denominators:
LCM of 7 and 72 is 504

Next, find the equivalent fraction of both fractional numbers with denominator 504
For the 1st fraction, since 7 × 72 = 504,
12/7 = 12 × 72/7 × 72 = 864/504
Likewise, for the 2nd fraction, since 72 × 7 = 504,
21/72 = 21 × 7/72 × 7 = 147/504
Add the two like fractions:
864/504 + 147/504 = 864 + 147/504 = 1011/504
1011/504 simplified gives 337/168
So, 12/7 + 21/72 = 337/168
In mixed form: 21/168

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