Add 54/15 and 35/21, Solve 3 9/15 + 1 14/21 as a fraction

Add 54/15 and 35/21

1^st number: 3 9/15, 2^nd number: 1 14/21

54/15 + 35/21 is 79/15.

Find the least common denominator or LCM of the two denominators:
LCM of 15 and 21 is 105

Next, find the equivalent fraction of both fractional numbers with denominator 105
For the 1st fraction, since 15 × 7 = 105,
54/15 = 54 × 7/15 × 7 = 378/105
Likewise, for the 2nd fraction, since 21 × 5 = 105,
35/21 = 35 × 5/21 × 5 = 175/105
Add the two like fractions:
378/105 + 175/105 = 378 + 175/105 = 553/105
553/105 simplified gives 79/15
So, 54/15 + 35/21 = 79/15
In mixed form: 54/15

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