Add 72/21 and 25/15, Solve 3 9/21 + 1 10/15 as a fraction

Add 72/21 and 25/15

1^st number: 3 9/21, 2^nd number: 1 10/15

72/21 + 25/15 is 107/21.

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,
72/21 = 72 × 5/21 × 5 = 360/105
Likewise, for the 2nd fraction, since 15 × 7 = 105,
25/15 = 25 × 7/15 × 7 = 175/105
Add the two like fractions:
360/105 + 175/105 = 360 + 175/105 = 535/105
535/105 simplified gives 107/21
So, 72/21 + 25/15 = 107/21
In mixed form: 52/21

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