Answer:
120+100+120+120+x+x+10=720 (given)
470+2x=720
2x=720-470
x=250/2
x=125
Step-by-step explanation:
Answer: r=8
Step by step: 6r+47=95
6r+47=95
-47. -47
6r=48
————
6. 6
R=8
Answer:
216
Step-by-step explanation:
Answer:
(11.242 ; 12.958)
Step-by-step explanation:
The confidence interval is obtained using the relation :
C. I = xbar ± Zcritical * s/√n
Given that ::
xbar = 12.1 ;
Standard deviation, s = 16.6
n = 1012
C. I = 12.1 ± 1.645 * (16.6/√1012)
C.I = 12.1 ± 0.8583881
C. I = 11.242 ; 12.958