Add 90/21 and 42/9, Solve 4 6/21 + 4 6/9 as a fraction

Add 90/21 and 42/9

1^st number: 4 6/21, 2^nd number: 4 6/9

90/21 + 42/9 is 188/21.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 9 is 63

Next, find the equivalent fraction of both fractional numbers with denominator 63
For the 1st fraction, since 21 × 3 = 63,
90/21 = 90 × 3/21 × 3 = 270/63
Likewise, for the 2nd fraction, since 9 × 7 = 63,
42/9 = 42 × 7/9 × 7 = 294/63
Add the two like fractions:
270/63 + 294/63 = 270 + 294/63 = 564/63
564/63 simplified gives 188/21
So, 90/21 + 42/9 = 188/21
In mixed form: 820/21

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