Suppose 80% of kids who visit a doctor have a fever, and 25% of kids with a fever have a sore throat. What's the probability that a kid who goes to the doctor has a fever and a sore throat?

Question

amina_soneviseth · Answer

To find compound probabilities like this multiply the individual probabilities.

For instance toss a coin twice what are the odds of heads both times?
(1/2)(1/2)=1/4

So rewrite your percentages as fractions or decimals and multiply to get your answer.

anonymous · Answer

so .80*.25?

amina_soneviseth · Answer

yes and make it a percentage. :D

PLEASE GIVE MEDALS IF THIS HELPED

anonymous · Answer

can you help me with 1 more question I'll give you a bunch of medals!

anonymous · Answer

a card is drawn at random from a standard deck of 52 cards find the following conditional probabilities
a)the card is a spade given that it is black
b)the card is black given that it is a spade
c) the card is a queen given that it is black
d) the card is a jack given that it is a face card

anonymous · Answer

I have a hard time with these "given that" problems

amina_soneviseth · Answer

@tofusoup  
a.)becuase theres like 13 black spades in a deck

IF THIS HELPED MEDAL AND FAN TY!

ybarrap · Answer

"Given That" problems mean that you ignore all other possibilities and treat only that particular subset of events.

For example, given that 

a)the card is a spade given that it is black

we take as the only possible events, the black cards. Of these black cards, how many are spades? If there are x black cards and y  of these are spades, then the probability of y given x is just $\cfrac{y}{x}$.