Add 48/18 and 30/21, Solve 2 12/18 + 1 9/21 as a fraction

Add 48/18 and 30/21

1^st number: 2 12/18, 2^nd number: 1 9/21

48/18 + 30/21 is 86/21.

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

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 18 × 7 = 126,
48/18 = 48 × 7/18 × 7 = 336/126
Likewise, for the 2nd fraction, since 21 × 6 = 126,
30/21 = 30 × 6/21 × 6 = 180/126
Add the two like fractions:
336/126 + 180/126 = 336 + 180/126 = 516/126
516/126 simplified gives 86/21
So, 48/18 + 30/21 = 86/21
In mixed form: 42/21

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