Add 80/21 and 21/60, Solve 3 17/21 + 21/60 as a fraction

Add 80/21 and 21/60

1^st number: 3 17/21, 2^nd number: 21/60

80/21 + 21/60 is 1747/420.

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,
80/21 = 80 × 20/21 × 20 = 1600/420
Likewise, for the 2nd fraction, since 60 × 7 = 420,
21/60 = 21 × 7/60 × 7 = 147/420
Add the two like fractions:
1600/420 + 147/420 = 1600 + 147/420 = 1747/420
So, 80/21 + 21/60 = 1747/420
In mixed form: 467/420

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