Add 21/35 and 80/60, Solve 21/35 + 1 20/60 as a fraction

Add 21/35 and 80/60

1^st number: 21/35, 2^nd number: 1 20/60

21/35 + 80/60 is 29/15.

Find the least common denominator or LCM of the two denominators:
LCM of 35 and 60 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 35 × 12 = 420,
21/35 = 21 × 12/35 × 12 = 252/420
Likewise, for the 2nd fraction, since 60 × 7 = 420,
80/60 = 80 × 7/60 × 7 = 560/420
Add the two like fractions:
252/420 + 560/420 = 252 + 560/420 = 812/420
812/420 simplified gives 29/15
So, 21/35 + 80/60 = 29/15
In mixed form: 114/15

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