Add 21/7 and 4/72, Solve 3 0/7 + 4/72 as a fraction

Add 21/7 and 4/72

1^st number: 3 0/7, 2^nd number: 4/72

21/7 + 4/72 is 55/18.

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,
21/7 = 21 × 72/7 × 72 = 1512/504
Likewise, for the 2nd fraction, since 72 × 7 = 504,
4/72 = 4 × 7/72 × 7 = 28/504
Add the two like fractions:
1512/504 + 28/504 = 1512 + 28/504 = 1540/504
1540/504 simplified gives 55/18
So, 21/7 + 4/72 = 55/18
In mixed form: 31/18

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