Add 27/21 and 81/90, Solve 1 6/21 + 81/90 as a fraction

Add 27/21 and 81/90

1^st number: 1 6/21, 2^nd number: 81/90

27/21 + 81/90 is 153/70.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 90 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 21 × 30 = 630,
27/21 = 27 × 30/21 × 30 = 810/630
Likewise, for the 2nd fraction, since 90 × 7 = 630,
81/90 = 81 × 7/90 × 7 = 567/630
Add the two like fractions:
810/630 + 567/630 = 810 + 567/630 = 1377/630
1377/630 simplified gives 153/70
So, 27/21 + 81/90 = 153/70
In mixed form: 213/70

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