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# A box contains 5 green, 4 yellow and 3 white balls. Three balls are drawn at random. What is the probability that they are not of same colour.

$\frac{52}{55}$

$\frac{3}{55}$

$\frac{41}{44}$

$\frac{3}{44}$

C. $\frac{41}{44}$
Total cases =${}^{12}c_{3}$
$=\frac{12×11×10}{3×2×1}=220$
Total cases of drawing same colour =${}^{5}c_{3}+{}^{4}c_{3}+{}^{3}c_{3}$
$\frac{5×4}{2×1}+4+1=15$
Probability of same colur $==\frac{15}{220}=\frac{3}{44}$
Probability of not same colur =$1-\frac{3}{44}$
=$\frac{41}{44}$