Add 1/42 and 21/18, Solve 1/42 + 1 3/18 as a fraction

Add 1/42 and 21/18

1^st number: 1/42, 2^nd number: 1 3/18

1/42 + 21/18 is 25/21.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 18 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 42 × 3 = 126,
1/42 = 1 × 3/42 × 3 = 3/126
Likewise, for the 2nd fraction, since 18 × 7 = 126,
21/18 = 21 × 7/18 × 7 = 147/126
Add the two like fractions:
3/126 + 147/126 = 3 + 147/126 = 150/126
150/126 simplified gives 25/21
So, 1/42 + 21/18 = 25/21
In mixed form: 14/21

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