Add 6/20 and 18/42, Solve 6/20 + 18/42 as a fraction

Add 6/20 and 18/42

6/20 + 18/42 is 51/70.

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,
6/20 = 6 × 21/20 × 21 = 126/420
Likewise, for the 2nd fraction, since 42 × 10 = 420,
18/42 = 18 × 10/42 × 10 = 180/420
Add the two like fractions:
126/420 + 180/420 = 126 + 180/420 = 306/420
306/420 simplified gives 51/70
So, 6/20 + 18/42 = 51/70

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