Add 30/75 and 75/21, Solve 30/75 + 3 12/21 as a fraction

Add 30/75 and 75/21

1^st number: 30/75, 2^nd number: 3 12/21

30/75 + 75/21 is 139/35.

Find the least common denominator or LCM of the two denominators:
LCM of 75 and 21 is 525

Next, find the equivalent fraction of both fractional numbers with denominator 525
For the 1st fraction, since 75 × 7 = 525,
30/75 = 30 × 7/75 × 7 = 210/525
Likewise, for the 2nd fraction, since 21 × 25 = 525,
75/21 = 75 × 25/21 × 25 = 1875/525
Add the two like fractions:
210/525 + 1875/525 = 210 + 1875/525 = 2085/525
2085/525 simplified gives 139/35
So, 30/75 + 75/21 = 139/35
In mixed form: 334/35

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