Add 25/21 and 12/18, Solve 1 4/21 + 12/18 as a fraction

Add 25/21 and 12/18

1^st number: 1 4/21, 2^nd number: 12/18

25/21 + 12/18 is 13/7.

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,
25/21 = 25 × 6/21 × 6 = 150/126
Likewise, for the 2nd fraction, since 18 × 7 = 126,
12/18 = 12 × 7/18 × 7 = 84/126
Add the two like fractions:
150/126 + 84/126 = 150 + 84/126 = 234/126
234/126 simplified gives 13/7
So, 25/21 + 12/18 = 13/7
In mixed form: 16/7

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