Add 54/10 and 21/84, Solve 5 4/10 + 21/84 as a fraction

Add 54/10 and 21/84

1^st number: 5 4/10, 2^nd number: 21/84

54/10 + 21/84 is 113/20.

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,
54/10 = 54 × 42/10 × 42 = 2268/420
Likewise, for the 2nd fraction, since 84 × 5 = 420,
21/84 = 21 × 5/84 × 5 = 105/420
Add the two like fractions:
2268/420 + 105/420 = 2268 + 105/420 = 2373/420
2373/420 simplified gives 113/20
So, 54/10 + 21/84 = 113/20
In mixed form: 513/20

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