Add 72/70 and 42/21, Solve 1 2/70 + 2 0/21 as a fraction

Add 72/70 and 42/21

1^st number: 1 2/70, 2^nd number: 2 0/21

72/70 + 42/21 is 106/35.

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,
72/70 = 72 × 3/70 × 3 = 216/210
Likewise, for the 2nd fraction, since 21 × 10 = 210,
42/21 = 42 × 10/21 × 10 = 420/210
Add the two like fractions:
216/210 + 420/210 = 216 + 420/210 = 636/210
636/210 simplified gives 106/35
So, 72/70 + 42/21 = 106/35
In mixed form: 31/35

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