Respuesta :
Answer:
The probability that 35 or more from this sample used Google Chrome as their browser is 0.9838.
Step-by-step explanation:
We are given that according to Statcounter, the Google Chrome browser controls 62.8% of the market share worldwide.
A random sample of 70 users was selected.
Let [tex]\hat p[/tex] = sample proportion of users who used Google Chrome as their browser.
The z-score probability distribution for the sample proportion is given by;
Z = [tex]\frac{\hat p-p}{\sqrt{\frac{\hat p(1-\hat p)}{n} } }[/tex] ~ N(0,1)
where, [tex]\hat p[/tex] = sample proportion = [tex]\frac{35}{70}[/tex] = 0.50
p = population proportion = 62.8%
n = sample of users = 70
Now, the probability that 35 or more from this sample used Google Chrome as their browser is given by = P( [tex]\hat p[/tex] [tex]\geq[/tex] 0.50)
P( [tex]\hat p[/tex] [tex]\geq[/tex] 0.50) = P( [tex]\frac{\hat p-p}{\sqrt{\frac{\hat p(1-\hat p)}{n} } }[/tex] [tex]\geq[/tex] [tex]\frac{0.50-0.628}{\sqrt{\frac{0.50(1-0.50)}{70} } }[/tex] ) = P(Z [tex]\geq[/tex] -2.14)
= P(Z [tex]\leq[/tex] 2.14) = 0.9838
The above probability is calculated by looking at the value of x = 2.14 in the z table which has an area of 0.9838.
