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

Add 28/21 and 21/45

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

28/21 + 21/45 is 9/5.

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,
21/45 = 21 × 7/45 × 7 = 147/315
Add the two like fractions:
420/315 + 147/315 = 420 + 147/315 = 567/315
567/315 simplified gives 9/5
So, 28/21 + 21/45 = 9/5
In mixed form: 14/5

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