Add 21/6 and 10/40, Solve 3 3/6 + 10/40 as a fraction

Add 21/6 and 10/40

1^st number: 3 3/6, 2^nd number: 10/40

21/6 + 10/40 is 15/4.

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,
10/40 = 10 × 3/40 × 3 = 30/120
Add the two like fractions:
420/120 + 30/120 = 420 + 30/120 = 450/120
450/120 simplified gives 15/4
So, 21/6 + 10/40 = 15/4
In mixed form: 33/4

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