Add 54/21 and 21/15, Solve 2 12/21 + 1 6/15 as a fraction

Add 54/21 and 21/15

1^st number: 2 12/21, 2^nd number: 1 6/15

54/21 + 21/15 is 139/35.

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

Next, find the equivalent fraction of both fractional numbers with denominator 105
For the 1st fraction, since 21 × 5 = 105,
54/21 = 54 × 5/21 × 5 = 270/105
Likewise, for the 2nd fraction, since 15 × 7 = 105,
21/15 = 21 × 7/15 × 7 = 147/105
Add the two like fractions:
270/105 + 147/105 = 270 + 147/105 = 417/105
417/105 simplified gives 139/35
So, 54/21 + 21/15 = 139/35
In mixed form: 334/35

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