Add 70/21 and 18/72, Solve 3 7/21 + 18/72 as a fraction

Add 70/21 and 18/72

1^st number: 3 7/21, 2^nd number: 18/72

70/21 + 18/72 is 43/12.

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,
18/72 = 18 × 7/72 × 7 = 126/504
Add the two like fractions:
1680/504 + 126/504 = 1680 + 126/504 = 1806/504
1806/504 simplified gives 43/12
So, 70/21 + 18/72 = 43/12
In mixed form: 37/12

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