Add 21/4 and 28/70, Solve 5 1/4 + 28/70 as a fraction

Add 21/4 and 28/70

1^st number: 5 1/4, 2^nd number: 28/70

21/4 + 28/70 is 113/20.

Find the least common denominator or LCM of the two denominators:
LCM of 4 and 70 is 140

Next, find the equivalent fraction of both fractional numbers with denominator 140
For the 1st fraction, since 4 × 35 = 140,
21/4 = 21 × 35/4 × 35 = 735/140
Likewise, for the 2nd fraction, since 70 × 2 = 140,
28/70 = 28 × 2/70 × 2 = 56/140
Add the two like fractions:
735/140 + 56/140 = 735 + 56/140 = 791/140
791/140 simplified gives 113/20
So, 21/4 + 28/70 = 113/20
In mixed form: 513/20

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