Add 10/42 and 28/20, Solve 10/42 + 1 8/20 as a fraction

Add 10/42 and 28/20

1^st number: 10/42, 2^nd number: 1 8/20

10/42 + 28/20 is 172/105.

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

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 42 × 10 = 420,
10/42 = 10 × 10/42 × 10 = 100/420
Likewise, for the 2nd fraction, since 20 × 21 = 420,
28/20 = 28 × 21/20 × 21 = 588/420
Add the two like fractions:
100/420 + 588/420 = 100 + 588/420 = 688/420
688/420 simplified gives 172/105
So, 10/42 + 28/20 = 172/105
In mixed form: 167/105

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