Add 21/6 and 30/40, Solve 3 3/6 + 30/40 as a fraction

Add 21/6 and 30/40

1^st number: 3 3/6, 2^nd number: 30/40

21/6 + 30/40 is 17/4.

Find the least common denominator or LCM of the two denominators:
LCM of 6 and 40 is 120

Next, find the equivalent fraction of both fractional numbers with denominator 120
For the 1st fraction, since 6 × 20 = 120,
21/6 = 21 × 20/6 × 20 = 420/120
Likewise, for the 2nd fraction, since 40 × 3 = 120,
30/40 = 30 × 3/40 × 3 = 90/120
Add the two like fractions:
420/120 + 90/120 = 420 + 90/120 = 510/120
510/120 simplified gives 17/4
So, 21/6 + 30/40 = 17/4
In mixed form: 41/4

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