Answer:
Step-by-step explanation:
a)
Number of sample, n = 100
p = 0.78
q = 1 - p = 1 - 0.78
q = 0.22
For a confidence level of 90%, the corresponding z value is 1.645.
The formula for determining the error bound for the proportion is
z × √pq/n
= 1.645 ×√(0.78 × 0.22)/100
= 1.645 × 0.0414 = 0.068
The upper boundary of the population proportion is
0.78 + 0.068 = 0.85
The lower boundary of the population proportion is
0.78 - 0.068 = 0.71
b) For a confidence level of 95%, the corresponding z value is 1.96.
Therefore,
= 1.96 ×√(0.78 × 0.22)/100
= 1.96 × 0.0414 = 0.081
The upper boundary of the population proportion is
0.78 + 0.081 = 0.86
The lower boundary of the population proportion is
0.78 - 0.081 = 0.7
Answer:81
Step-by-step explanation: 9*1= 9 9*2= 18 9*3 = 27 9*4= 36 9*5=45 9*6 = 54 9*7=63 9*8= 72 9*9 81 9*10= 90
Answer:
4 t - 7 = 2 t+ 13 is the required equation.
The number of race medals Tara has is t = 20 medals.
Step-by-step explanation:
Let the number of medals Tara has = t medals
So, the number of medal Anita has = 4( Medals of Tara) - 7
= 4t - 7
And the number of medals Gary has = 2 times (Medals of Tara) + 13
= 2(t) + 13 = 2t + 13
Now, Annita and Gary has same number of medals.
⇒ 4t - 7 = 2t+ 13
or, 4t - 2t = 7 + 13
⇒ 2t = 20
⇒ t = 20/2 = 10
or t = 10
Hence, the number of race medals Tara has is t = 20 medals