Add 21/84 and 81/10, Solve 21/84 + 8 1/10 as a fraction

Add 21/84 and 81/10

1^st number: 21/84, 2^nd number: 8 1/10

21/84 + 81/10 is 167/20.

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

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 84 × 5 = 420,
21/84 = 21 × 5/84 × 5 = 105/420
Likewise, for the 2nd fraction, since 10 × 42 = 420,
81/10 = 81 × 42/10 × 42 = 3402/420
Add the two like fractions:
105/420 + 3402/420 = 105 + 3402/420 = 3507/420
3507/420 simplified gives 167/20
So, 21/84 + 81/10 = 167/20
In mixed form: 87/20

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