Add 70/21 and 12/72, Solve 3 7/21 + 12/72 as a fraction

Add 70/21 and 12/72

1^st number: 3 7/21, 2^nd number: 12/72

70/21 + 12/72 is 7/2.

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,
70/21 = 70 × 24/21 × 24 = 1680/504
Likewise, for the 2nd fraction, since 72 × 7 = 504,
12/72 = 12 × 7/72 × 7 = 84/504
Add the two like fractions:
1680/504 + 84/504 = 1680 + 84/504 = 1764/504
1764/504 simplified gives 7/2
So, 70/21 + 12/72 = 7/2
In mixed form: 31/2

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