Olympiad Maths Prep

Track / Stage 4 / 40 of 340 #300 of 2000

Problem 300

AMC 12 late, AIME early
Combinatorics Difficulty 4.6 Find the answer

13. Two different numbers are randomly selected from the set {2,1,0,3,4,5}\{-2,-1,0,3,4,5\} and multiplied. The probability that the product is 0 is ( ).
(A) 16\frac{1}{6}
(B) 15\frac{1}{5}
(C) 14\frac{1}{4}
(D) 13\frac{1}{3}
(E) 12\frac{1}{2}

Official solution

13. D.
P=C51C62=56×52=13 P=\frac{\mathrm{C}_{5}^{1}}{\mathrm{C}_{6}^{2}}=\frac{5}{\frac{6 \times 5}{2}}=\frac{1}{3}

Source: NuminaMath-1.5, licensed Apache-2.0. Statement and solution reproduced as published; topic, difficulty and ordering added by this site.