Add 36/21 and 81/18, Solve 1 15/21 + 4 9/18 as a fraction

Add 36/21 and 81/18

1^st number: 1 15/21, 2^nd number: 4 9/18

36/21 + 81/18 is 87/14.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 18 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 21 × 6 = 126,
36/21 = 36 × 6/21 × 6 = 216/126
Likewise, for the 2nd fraction, since 18 × 7 = 126,
81/18 = 81 × 7/18 × 7 = 567/126
Add the two like fractions:
216/126 + 567/126 = 216 + 567/126 = 783/126
783/126 simplified gives 87/14
So, 36/21 + 81/18 = 87/14
In mixed form: 63/14

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