Add 81/20 and 70/42, Solve 4 1/20 + 1 28/42 as a fraction

Add 81/20 and 70/42

1^st number: 4 1/20, 2^nd number: 1 28/42

81/20 + 70/42 is 343/60.

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,
81/20 = 81 × 21/20 × 21 = 1701/420
Likewise, for the 2nd fraction, since 42 × 10 = 420,
70/42 = 70 × 10/42 × 10 = 700/420
Add the two like fractions:
1701/420 + 700/420 = 1701 + 700/420 = 2401/420
2401/420 simplified gives 343/60
So, 81/20 + 70/42 = 343/60
In mixed form: 543/60

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