Buratino, Fox Alice and Kot Basilio found a treasure with 10 gold coins. The fox Alice took away 5 coins, Kot Basilio 3 coins, Buratino 2 coins. It is known that two coins false. To find the probability that at least Buratino got one of them. Otvet to round with an accuracy up to 0.01.

Let's designate A– "By Buratino two coins and at least one false got". n=C210=10! / (10–2)! · 2! =10·9/2=45 ways to choose two coins. m=C81 · C12+C22=8·2+1=17 ways to choose though one false (one or both) r (A) =m/n=17/45=0.37777... p=0.38
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