Add 75/21 and 4/45, Solve 3 12/21 + 4/45 as a fraction

Add 75/21 and 4/45

1^st number: 3 12/21, 2^nd number: 4/45

75/21 + 4/45 is 1153/315.

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,
75/21 = 75 × 15/21 × 15 = 1125/315
Likewise, for the 2nd fraction, since 45 × 7 = 315,
4/45 = 4 × 7/45 × 7 = 28/315
Add the two like fractions:
1125/315 + 28/315 = 1125 + 28/315 = 1153/315
So, 75/21 + 4/45 = 1153/315
In mixed form: 3208/315

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