Add 81/42 and 16/20, Solve 1 39/42 + 16/20 as a fraction

Add 81/42 and 16/20

1^st number: 1 39/42, 2^nd number: 16/20

81/42 + 16/20 is 191/70.

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,
81/42 = 81 × 10/42 × 10 = 810/420
Likewise, for the 2nd fraction, since 20 × 21 = 420,
16/20 = 16 × 21/20 × 21 = 336/420
Add the two like fractions:
810/420 + 336/420 = 810 + 336/420 = 1146/420
1146/420 simplified gives 191/70
So, 81/42 + 16/20 = 191/70
In mixed form: 251/70

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