Add 40/6 and 21/90, Solve 6 4/6 + 21/90 as a fraction

Add 40/6 and 21/90

1^st number: 6 4/6, 2^nd number: 21/90

40/6 + 21/90 is 69/10.

Find the least common denominator or LCM of the two denominators:
LCM of 6 and 90 is 90

Next, find the equivalent fraction of both fractional numbers with denominator 90
For the 1st fraction, since 6 × 15 = 90,
40/6 = 40 × 15/6 × 15 = 600/90
Likewise, for the 2nd fraction, since 90 × 1 = 90,
21/90 = 21 × 1/90 × 1 = 21/90
Add the two like fractions:
600/90 + 21/90 = 600 + 21/90 = 621/90
621/90 simplified gives 69/10
So, 40/6 + 21/90 = 69/10
In mixed form: 69/10

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