Add 1/20 and 45/42, Solve 1/20 + 1 3/42 as a fraction

Add 1/20 and 45/42

1^st number: 1/20, 2^nd number: 1 3/42

1/20 + 45/42 is 157/140.

Find the least common denominator or LCM of the two denominators:
LCM of 20 and 42 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 20 × 21 = 420,
1/20 = 1 × 21/20 × 21 = 21/420
Likewise, for the 2nd fraction, since 42 × 10 = 420,
45/42 = 45 × 10/42 × 10 = 450/420
Add the two like fractions:
21/420 + 450/420 = 21 + 450/420 = 471/420
471/420 simplified gives 157/140
So, 1/20 + 45/42 = 157/140
In mixed form: 117/140

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