Add 20/21 and 42/8, Solve 20/21 + 5 2/8 as a fraction

Add 20/21 and 42/8

1^st number: 20/21, 2^nd number: 5 2/8

20/21 + 42/8 is 521/84.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 8 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 21 × 8 = 168,
20/21 = 20 × 8/21 × 8 = 160/168
Likewise, for the 2nd fraction, since 8 × 21 = 168,
42/8 = 42 × 21/8 × 21 = 882/168
Add the two like fractions:
160/168 + 882/168 = 160 + 882/168 = 1042/168
1042/168 simplified gives 521/84
So, 20/21 + 42/8 = 521/84
In mixed form: 617/84

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