Add 30/70 and 84/72, Solve 30/70 + 1 12/72 as a fraction

Add 30/70 and 84/72

1^st number: 30/70, 2^nd number: 1 12/72

30/70 + 84/72 is 67/42.

Find the least common denominator or LCM of the two denominators:
LCM of 70 and 72 is 2520

Next, find the equivalent fraction of both fractional numbers with denominator 2520
For the 1st fraction, since 70 × 36 = 2520,
30/70 = 30 × 36/70 × 36 = 1080/2520
Likewise, for the 2nd fraction, since 72 × 35 = 2520,
84/72 = 84 × 35/72 × 35 = 2940/2520
Add the two like fractions:
1080/2520 + 2940/2520 = 1080 + 2940/2520 = 4020/2520
4020/2520 simplified gives 67/42
So, 30/70 + 84/72 = 67/42
In mixed form: 125/42

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