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

Add 72/70 and 21/42

1^st number: 1 2/70, 2^nd number: 21/42

72/70 + 21/42 is 107/70.

Find the least common denominator or LCM of the two denominators:
LCM of 70 and 42 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 42 × 5 = 210,
21/42 = 21 × 5/42 × 5 = 105/210
Add the two like fractions:
216/210 + 105/210 = 216 + 105/210 = 321/210
321/210 simplified gives 107/70
So, 72/70 + 21/42 = 107/70
In mixed form: 137/70

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