Add 9/21 and 70/45, Solve 9/21 + 1 25/45 as a fraction

Add 9/21 and 70/45

1^st number: 9/21, 2^nd number: 1 25/45

9/21 + 70/45 is 125/63.

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,
9/21 = 9 × 15/21 × 15 = 135/315
Likewise, for the 2nd fraction, since 45 × 7 = 315,
70/45 = 70 × 7/45 × 7 = 490/315
Add the two like fractions:
135/315 + 490/315 = 135 + 490/315 = 625/315
625/315 simplified gives 125/63
So, 9/21 + 70/45 = 125/63
In mixed form: 162/63

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