Add 28/21 and 5/70, Solve 1 7/21 + 5/70 as a fraction

Add 28/21 and 5/70

1^st number: 1 7/21, 2^nd number: 5/70

28/21 + 5/70 is 59/42.

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

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 21 × 10 = 210,
28/21 = 28 × 10/21 × 10 = 280/210
Likewise, for the 2nd fraction, since 70 × 3 = 210,
5/70 = 5 × 3/70 × 3 = 15/210
Add the two like fractions:
280/210 + 15/210 = 280 + 15/210 = 295/210
295/210 simplified gives 59/42
So, 28/21 + 5/70 = 59/42
In mixed form: 117/42

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