Add 36/10 and 21/84, Solve 3 6/10 + 21/84 as a fraction

Add 36/10 and 21/84

1^st number: 3 6/10, 2^nd number: 21/84

36/10 + 21/84 is 77/20.

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,
36/10 = 36 × 42/10 × 42 = 1512/420
Likewise, for the 2nd fraction, since 84 × 5 = 420,
21/84 = 21 × 5/84 × 5 = 105/420
Add the two like fractions:
1512/420 + 105/420 = 1512 + 105/420 = 1617/420
1617/420 simplified gives 77/20
So, 36/10 + 21/84 = 77/20
In mixed form: 317/20

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