Add 81/21 and 10/72, Solve 3 18/21 + 10/72 as a fraction

Add 81/21 and 10/72

1^st number: 3 18/21, 2^nd number: 10/72

81/21 + 10/72 is 1007/252.

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,
81/21 = 81 × 24/21 × 24 = 1944/504
Likewise, for the 2nd fraction, since 72 × 7 = 504,
10/72 = 10 × 7/72 × 7 = 70/504
Add the two like fractions:
1944/504 + 70/504 = 1944 + 70/504 = 2014/504
2014/504 simplified gives 1007/252
So, 81/21 + 10/72 = 1007/252
In mixed form: 3251/252

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