Add 28/42 and 81/60, Solve 28/42 + 1 21/60 as a fraction

Add 28/42 and 81/60

1^st number: 28/42, 2^nd number: 1 21/60

28/42 + 81/60 is 121/60.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 60 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 42 × 10 = 420,
28/42 = 28 × 10/42 × 10 = 280/420
Likewise, for the 2nd fraction, since 60 × 7 = 420,
81/60 = 81 × 7/60 × 7 = 567/420
Add the two like fractions:
280/420 + 567/420 = 280 + 567/420 = 847/420
847/420 simplified gives 121/60
So, 28/42 + 81/60 = 121/60
In mixed form: 21/60

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