Add 18/21 and 21/15, Solve 18/21 + 1 6/15 as a fraction

Add 18/21 and 21/15

1^st number: 18/21, 2^nd number: 1 6/15

18/21 + 21/15 is 79/35.

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,
18/21 = 18 × 5/21 × 5 = 90/105
Likewise, for the 2nd fraction, since 15 × 7 = 105,
21/15 = 21 × 7/15 × 7 = 147/105
Add the two like fractions:
90/105 + 147/105 = 90 + 147/105 = 237/105
237/105 simplified gives 79/35
So, 18/21 + 21/15 = 79/35
In mixed form: 29/35

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