Sorry this took so long! I managed to do everything except for the parts involving standard deviation. (I tried but I couldn't quite figure it out.)
~Hope this helps!~
131.9.
to the nearest tenth means to the nearest 0.*
I’m sorry. But none of your choices are correct. The correct answer would be 3 and 4. Further more explaining= 3+ 2 times 4 is 24. 2x= 4. That equals 8 and 3 times 8 is 24
The tree diagram for the probability is shown below
P(Clay|Positive) is read 'Probability of Clay given the result is Positive'.
This is a case of conditional probability.
The formula for conditional probability is given as
P(Clay|Positive) = P(Clay∩Positive) ÷ P(Positive)
P(Clay∩Positive) = 0.21×0.48 = 0.1008
P(Positive) = P(Rock∩Positive) + P(Clay∩Positive) + P(Sand∩Positive)
P(Positive) = (0.53×0.53) + (0.21×0.48) + (0.26×0.75)
P(Positive) = 0.2809 + 0.1008 + 0.195
P(Positive) = 0.5767
Hence,
P(Clay|Positive) = 0.1008÷0.5767 = 0.175 (rounded to 3 decimal place)
9/xy + x^2/y = (9+x^3)/xy