Add 10/21 and 28/45, Solve 10/21 + 28/45 as a fraction

Add 10/21 and 28/45

10/21 + 28/45 is 346/315.

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,
10/21 = 10 × 15/21 × 15 = 150/315
Likewise, for the 2nd fraction, since 45 × 7 = 315,
28/45 = 28 × 7/45 × 7 = 196/315
Add the two like fractions:
150/315 + 196/315 = 150 + 196/315 = 346/315
So, 10/21 + 28/45 = 346/315
In mixed form: 131/315

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