Respuesta :
Answer:
P ( X > 1800) = 0.1734
Step-by-step explanation:
Given:-
- The mean, u = 1497
- The standard deviation, s.d = 322
Find:-
P(X>1800)
Solution:-
- We will denote a random variable X that follows a normal distribution for the SAT scores in 2014 with parameters mean (u) and standard deviation (s.d) as follows:
X ~ N ( 1497 , 322 )
- The following probability can be calculated by first computing the Z-score value:
P ( X < x ) = P ( X < Z )
Where,
Z = ( x - u ) / s.d
- P(X > 1800) have the corresponding Z-score value:
Z = ( 1800 - 1497 ) / 322
Z = 0.941
- Hence, using Z-table:
P ( X > 1800) = 1 - P ( Z < 0.9471 )
P ( X > 1800) = 1 - 0.8266
P ( X > 1800) = 0.1734
Otras preguntas
