Add 18/28 and 81/60, Solve 18/28 + 1 21/60 as a fraction

Add 18/28 and 81/60

1^st number: 18/28, 2^nd number: 1 21/60

18/28 + 81/60 is 279/140.

Find the least common denominator or LCM of the two denominators:
LCM of 28 and 60 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 28 × 15 = 420,
18/28 = 18 × 15/28 × 15 = 270/420
Likewise, for the 2nd fraction, since 60 × 7 = 420,
81/60 = 81 × 7/60 × 7 = 567/420
Add the two like fractions:
270/420 + 567/420 = 270 + 567/420 = 837/420
837/420 simplified gives 279/140
So, 18/28 + 81/60 = 279/140
In mixed form: 1139/140

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