Add 21/28 and 28/8, Solve 21/28 + 3 4/8 as a fraction

Add 21/28 and 28/8

1^st number: 21/28, 2^nd number: 3 4/8

21/28 + 28/8 is 17/4.

Find the least common denominator or LCM of the two denominators:
LCM of 28 and 8 is 56

Next, find the equivalent fraction of both fractional numbers with denominator 56
For the 1st fraction, since 28 × 2 = 56,
21/28 = 21 × 2/28 × 2 = 42/56
Likewise, for the 2nd fraction, since 8 × 7 = 56,
28/8 = 28 × 7/8 × 7 = 196/56
Add the two like fractions:
42/56 + 196/56 = 42 + 196/56 = 238/56
238/56 simplified gives 17/4
So, 21/28 + 28/8 = 17/4
In mixed form: 41/4

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