Add 21/28 and 90/63, Solve 21/28 + 1 27/63 as a fraction

Add 21/28 and 90/63

1^st number: 21/28, 2^nd number: 1 27/63

21/28 + 90/63 is 61/28.

Find the least common denominator or LCM of the two denominators:
LCM of 28 and 63 is 252

Next, find the equivalent fraction of both fractional numbers with denominator 252
For the 1st fraction, since 28 × 9 = 252,
21/28 = 21 × 9/28 × 9 = 189/252
Likewise, for the 2nd fraction, since 63 × 4 = 252,
90/63 = 90 × 4/63 × 4 = 360/252
Add the two like fractions:
189/252 + 360/252 = 189 + 360/252 = 549/252
549/252 simplified gives 61/28
So, 21/28 + 90/63 = 61/28
In mixed form: 25/28

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