Add 18/10 and 21/84, Solve 1 8/10 + 21/84 as a fraction

Add 18/10 and 21/84

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

18/10 + 21/84 is 41/20.

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,
18/10 = 18 × 42/10 × 42 = 756/420
Likewise, for the 2nd fraction, since 84 × 5 = 420,
21/84 = 21 × 5/84 × 5 = 105/420
Add the two like fractions:
756/420 + 105/420 = 756 + 105/420 = 861/420
861/420 simplified gives 41/20
So, 18/10 + 21/84 = 41/20
In mixed form: 21/20

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