Add 5/21 and 98/70, Solve 5/21 + 1 28/70 as a fraction

Add 5/21 and 98/70

1^st number: 5/21, 2^nd number: 1 28/70

5/21 + 98/70 is 172/105.

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,
5/21 = 5 × 10/21 × 10 = 50/210
Likewise, for the 2nd fraction, since 70 × 3 = 210,
98/70 = 98 × 3/70 × 3 = 294/210
Add the two like fractions:
50/210 + 294/210 = 50 + 294/210 = 344/210
344/210 simplified gives 172/105
So, 5/21 + 98/70 = 172/105
In mixed form: 167/105

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