Add 21/10 and 21/84, Solve 2 1/10 + 21/84 as a fraction

Add 21/10 and 21/84

1^st number: 2 1/10, 2^nd number: 21/84

21/10 + 21/84 is 47/20.

Find the least common denominator or LCM of the two denominators:
LCM of 10 and 84 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 10 × 42 = 420,
21/10 = 21 × 42/10 × 42 = 882/420
Likewise, for the 2nd fraction, since 84 × 5 = 420,
21/84 = 21 × 5/84 × 5 = 105/420
Add the two like fractions:
882/420 + 105/420 = 882 + 105/420 = 987/420
987/420 simplified gives 47/20
So, 21/10 + 21/84 = 47/20
In mixed form: 27/20

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