we have
------> equation 
------> equation 
Multiply by
the equation 
------> equation 
Sum equation
and equation 

Substitute the value of x in the equation 

therefore
the answer is the option B

Answer:
543
Step-by-step explanation:
The 33rd percentile corresponds to a score of 542.4. In order for a score to be within the top 67%, it must be above that value. The least integer above that value is 543.
Answer:
4
Step-by-step explanation:
i could be wrong