Add 18/75 and 75/21, Solve 18/75 + 3 12/21 as a fraction

Add 18/75 and 75/21

1^st number: 18/75, 2^nd number: 3 12/21

18/75 + 75/21 is 667/175.

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,
18/75 = 18 × 7/75 × 7 = 126/525
Likewise, for the 2nd fraction, since 21 × 25 = 525,
75/21 = 75 × 25/21 × 25 = 1875/525
Add the two like fractions:
126/525 + 1875/525 = 126 + 1875/525 = 2001/525
2001/525 simplified gives 667/175
So, 18/75 + 75/21 = 667/175
In mixed form: 3142/175

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