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Calculate conditional probability


Pedro observed what customers ordered at his ice cream shop and found the following probabilities:
P(vanilla)=0.3P(sundae)=0.2P(vanilla and sundae)=0.15\begin{aligned} &P(\text{vanilla})=0.3 \\\\ &P(\text{sundae})=0.2 \\\\ &P(\text{vanilla and sundae})=0.15 \end{aligned}
Find the probability that a customer ordered vanilla ice cream given they ordered a sundae.
P, left parenthesis, start text, v, a, n, i, l, l, a, space, end text, vertical bar, start text, space, s, u, n, d, a, e, end text, right parenthesis, equals
  • Your answer should be
  • an integer, like 6
  • a simplified proper fraction, like 3, slash, 5
  • a simplified improper fraction, like 7, slash, 4
  • a mixed number, like 1, space, 3, slash, 4
  • an exact decimal, like 0, point, 75
  • a multiple of pi, like 12, space, start text, p, i, end text or 2, slash, 3, space, start text, p, i, end text