Add 21/4 and 4/80, Solve 5 1/4 + 4/80 as a fraction

Add 21/4 and 4/80

1^st number: 5 1/4, 2^nd number: 4/80

21/4 + 4/80 is 53/10.

Find the least common denominator or LCM of the two denominators:
LCM of 4 and 80 is 80

Next, find the equivalent fraction of both fractional numbers with denominator 80
For the 1st fraction, since 4 × 20 = 80,
21/4 = 21 × 20/4 × 20 = 420/80
Likewise, for the 2nd fraction, since 80 × 1 = 80,
4/80 = 4 × 1/80 × 1 = 4/80
Add the two like fractions:
420/80 + 4/80 = 420 + 4/80 = 424/80
424/80 simplified gives 53/10
So, 21/4 + 4/80 = 53/10
In mixed form: 53/10

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