Add 15/9 and 63/42, Solve 1 6/9 + 1 21/42 as a fraction

Add 15/9 and 63/42

1^st number: 1 6/9, 2^nd number: 1 21/42

15/9 + 63/42 is 19/6.

Find the least common denominator or LCM of the two denominators:
LCM of 9 and 42 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 9 × 14 = 126,
15/9 = 15 × 14/9 × 14 = 210/126
Likewise, for the 2nd fraction, since 42 × 3 = 126,
63/42 = 63 × 3/42 × 3 = 189/126
Add the two like fractions:
210/126 + 189/126 = 210 + 189/126 = 399/126
399/126 simplified gives 19/6
So, 15/9 + 63/42 = 19/6
In mixed form: 31/6

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