Add 28/21 and 25/8, Solve 1 7/21 + 3 1/8 as a fraction

Add 28/21 and 25/8

1^st number: 1 7/21, 2^nd number: 3 1/8

28/21 + 25/8 is 107/24.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 8 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 21 × 8 = 168,
28/21 = 28 × 8/21 × 8 = 224/168
Likewise, for the 2nd fraction, since 8 × 21 = 168,
25/8 = 25 × 21/8 × 21 = 525/168
Add the two like fractions:
224/168 + 525/168 = 224 + 525/168 = 749/168
749/168 simplified gives 107/24
So, 28/21 + 25/8 = 107/24
In mixed form: 411/24

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