Add 70/21 and 28/72, Solve 3 7/21 + 28/72 as a fraction

Add 70/21 and 28/72

1^st number: 3 7/21, 2^nd number: 28/72

70/21 + 28/72 is 67/18.

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,
28/72 = 28 × 7/72 × 7 = 196/504
Add the two like fractions:
1680/504 + 196/504 = 1680 + 196/504 = 1876/504
1876/504 simplified gives 67/18
So, 70/21 + 28/72 = 67/18
In mixed form: 313/18

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