Add 27/21 and 90/63, Solve 1 6/21 + 1 27/63 as a fraction

Add 27/21 and 90/63

1^st number: 1 6/21, 2^nd number: 1 27/63

27/21 + 90/63 is 19/7.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 63 is 63

Next, find the equivalent fraction of both fractional numbers with denominator 63
For the 1st fraction, since 21 × 3 = 63,
27/21 = 27 × 3/21 × 3 = 81/63
Likewise, for the 2nd fraction, since 63 × 1 = 63,
90/63 = 90 × 1/63 × 1 = 90/63
Add the two like fractions:
81/63 + 90/63 = 81 + 90/63 = 171/63
171/63 simplified gives 19/7
So, 27/21 + 90/63 = 19/7
In mixed form: 25/7

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