Add 90/70 and 21/9, Solve 1 20/70 + 2 3/9 as a fraction

Add 90/70 and 21/9

1^st number: 1 20/70, 2^nd number: 2 3/9

90/70 + 21/9 is 76/21.

Find the least common denominator or LCM of the two denominators:
LCM of 70 and 9 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 70 × 9 = 630,
90/70 = 90 × 9/70 × 9 = 810/630
Likewise, for the 2nd fraction, since 9 × 70 = 630,
21/9 = 21 × 70/9 × 70 = 1470/630
Add the two like fractions:
810/630 + 1470/630 = 810 + 1470/630 = 2280/630
2280/630 simplified gives 76/21
So, 90/70 + 21/9 = 76/21
In mixed form: 313/21

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