Add 80/70 and 84/63, Solve 1 10/70 + 1 21/63 as a fraction

Add 80/70 and 84/63

1^st number: 1 10/70, 2^nd number: 1 21/63

80/70 + 84/63 is 52/21.

Find the least common denominator or LCM of the two denominators:
LCM of 70 and 63 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 70 × 9 = 630,
80/70 = 80 × 9/70 × 9 = 720/630
Likewise, for the 2nd fraction, since 63 × 10 = 630,
84/63 = 84 × 10/63 × 10 = 840/630
Add the two like fractions:
720/630 + 840/630 = 720 + 840/630 = 1560/630
1560/630 simplified gives 52/21
So, 80/70 + 84/63 = 52/21
In mixed form: 210/21

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