Add 10/21 and 80/60, Solve 10/21 + 1 20/60 as a fraction

Add 10/21 and 80/60

1^st number: 10/21, 2^nd number: 1 20/60

10/21 + 80/60 is 38/21.

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

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 21 × 20 = 420,
10/21 = 10 × 20/21 × 20 = 200/420
Likewise, for the 2nd fraction, since 60 × 7 = 420,
80/60 = 80 × 7/60 × 7 = 560/420
Add the two like fractions:
200/420 + 560/420 = 200 + 560/420 = 760/420
760/420 simplified gives 38/21
So, 10/21 + 80/60 = 38/21
In mixed form: 117/21

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