Add 28/21 and 8/45, Solve 1 7/21 + 8/45 as a fraction

Add 28/21 and 8/45

1^st number: 1 7/21, 2^nd number: 8/45

28/21 + 8/45 is 68/45.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 45 is 315

Next, find the equivalent fraction of both fractional numbers with denominator 315
For the 1st fraction, since 21 × 15 = 315,
28/21 = 28 × 15/21 × 15 = 420/315
Likewise, for the 2nd fraction, since 45 × 7 = 315,
8/45 = 8 × 7/45 × 7 = 56/315
Add the two like fractions:
420/315 + 56/315 = 420 + 56/315 = 476/315
476/315 simplified gives 68/45
So, 28/21 + 8/45 = 68/45
In mixed form: 123/45

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