From a large study of German children of Caucasian descent, it was found that 40% have brown hair, 20% have freckles, and 15% have brown hair and freckles. Let B be the event that a German child of Caucasian descent has brown hair. Let F be the event that a German child of Caucasian descent has freckles.

What is the probability that a randomly selected German child of Caucasian descent has freckles given that the child does not have brown hair?

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