Add 48/15 and 81/21, Solve 3 3/15 + 3 18/21 as a fraction

Add 48/15 and 81/21

1^st number: 3 3/15, 2^nd number: 3 18/21

48/15 + 81/21 is 247/35.

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,
48/15 = 48 × 7/15 × 7 = 336/105
Likewise, for the 2nd fraction, since 21 × 5 = 105,
81/21 = 81 × 5/21 × 5 = 405/105
Add the two like fractions:
336/105 + 405/105 = 336 + 405/105 = 741/105
741/105 simplified gives 247/35
So, 48/15 + 81/21 = 247/35
In mixed form: 72/35

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