Add 90/63 and 21/70, Solve 1 27/63 + 21/70 as a fraction

Add 90/63 and 21/70

1^st number: 1 27/63, 2^nd number: 21/70

90/63 + 21/70 is 121/70.

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

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 63 × 10 = 630,
90/63 = 90 × 10/63 × 10 = 900/630
Likewise, for the 2nd fraction, since 70 × 9 = 630,
21/70 = 21 × 9/70 × 9 = 189/630
Add the two like fractions:
900/630 + 189/630 = 900 + 189/630 = 1089/630
1089/630 simplified gives 121/70
So, 90/63 + 21/70 = 121/70
In mixed form: 151/70

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