Add 36/21 and 42/9, Solve 1 15/21 + 4 6/9 as a fraction

Add 36/21 and 42/9

1^st number: 1 15/21, 2^nd number: 4 6/9

36/21 + 42/9 is 134/21.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 9 is 63

Next, find the equivalent fraction of both fractional numbers with denominator 63
For the 1st fraction, since 21 × 3 = 63,
36/21 = 36 × 3/21 × 3 = 108/63
Likewise, for the 2nd fraction, since 9 × 7 = 63,
42/9 = 42 × 7/9 × 7 = 294/63
Add the two like fractions:
108/63 + 294/63 = 108 + 294/63 = 402/63
402/63 simplified gives 134/21
So, 36/21 + 42/9 = 134/21
In mixed form: 68/21

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