Add 21/6 and 42/80, Solve 3 3/6 + 42/80 as a fraction

Add 21/6 and 42/80

1^st number: 3 3/6, 2^nd number: 42/80

21/6 + 42/80 is 161/40.

Find the least common denominator or LCM of the two denominators:
LCM of 6 and 80 is 240

Next, find the equivalent fraction of both fractional numbers with denominator 240
For the 1st fraction, since 6 × 40 = 240,
21/6 = 21 × 40/6 × 40 = 840/240
Likewise, for the 2nd fraction, since 80 × 3 = 240,
42/80 = 42 × 3/80 × 3 = 126/240
Add the two like fractions:
840/240 + 126/240 = 840 + 126/240 = 966/240
966/240 simplified gives 161/40
So, 21/6 + 42/80 = 161/40
In mixed form: 41/40

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