Add 18/70 and 75/21, Solve 18/70 + 3 12/21 as a fraction

Add 18/70 and 75/21

1^st number: 18/70, 2^nd number: 3 12/21

18/70 + 75/21 is 134/35.

Find the least common denominator or LCM of the two denominators:
LCM of 70 and 21 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 70 × 3 = 210,
18/70 = 18 × 3/70 × 3 = 54/210
Likewise, for the 2nd fraction, since 21 × 10 = 210,
75/21 = 75 × 10/21 × 10 = 750/210
Add the two like fractions:
54/210 + 750/210 = 54 + 750/210 = 804/210
804/210 simplified gives 134/35
So, 18/70 + 75/21 = 134/35
In mixed form: 329/35

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