Add 24/45 and 75/21, Solve 24/45 + 3 12/21 as a fraction

Add 24/45 and 75/21

1^st number: 24/45, 2^nd number: 3 12/21

24/45 + 75/21 is 431/105.

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

Next, find the equivalent fraction of both fractional numbers with denominator 315
For the 1st fraction, since 45 × 7 = 315,
24/45 = 24 × 7/45 × 7 = 168/315
Likewise, for the 2nd fraction, since 21 × 15 = 315,
75/21 = 75 × 15/21 × 15 = 1125/315
Add the two like fractions:
168/315 + 1125/315 = 168 + 1125/315 = 1293/315
1293/315 simplified gives 431/105
So, 24/45 + 75/21 = 431/105
In mixed form: 411/105

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