Answer:
The probability that your friend had sprinkles given that he had chocolate [tex](P(S|C))[/tex] is approximately 0.357 or 0.36 if you round it to 2 decimals.
Step-by-step explanation:
Let's define the following events:
C = "Your friends like chocolate flavor"
S = "Your friends like sprinkles topping"
We also know that [tex]P(S) = 0.7[/tex], [tex]P(C) = 0.4[/tex] and [tex]P(S \cap C) = 0.25[/tex]. We are interested in the probability of given that your friend had chocalate what is the probability that he also likes sprinkles, in other words we want [tex]P(S|C)[/tex]. Note that,
[tex]P(S|C) = \frac{P(S \cap C)}{P(C)} = \frac{0.25}{0.70} \approx 0.357 \approx 0.36[/tex]