Add 12/60 and 28/21, Solve 12/60 + 1 7/21 as a fraction

Add 12/60 and 28/21

1^st number: 12/60, 2^nd number: 1 7/21

12/60 + 28/21 is 23/15.

Find the least common denominator or LCM of the two denominators:
LCM of 60 and 21 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 60 × 7 = 420,
12/60 = 12 × 7/60 × 7 = 84/420
Likewise, for the 2nd fraction, since 21 × 20 = 420,
28/21 = 28 × 20/21 × 20 = 560/420
Add the two like fractions:
84/420 + 560/420 = 84 + 560/420 = 644/420
644/420 simplified gives 23/15
So, 12/60 + 28/21 = 23/15
In mixed form: 18/15

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