He’s 1.5 away from his original starting
Complete question :
The Harris Poll conducted a survey in which they asked, "How many tattoos do you currently have on your body?" Of the 1205 males surveyed, 181 responded that they had at least one tattoo. Of the 1097 females surveyed, 143 responded that they had at least one tattoo. Construct a 95% confidence interval to judge whether the proportion of males that have at least one tattoo differs significantly from the proportion of females that have at least one tattoo. Interpret the interval.
Answer:
(−0.0085 ; 0.0481)
Step-by-step explanation:
Given that :
n1 = 1205 ; x1 = 181 ; n2 = 1097 ; x2 = 143 ; α = 95%
Zα/2 = 1.96 ( Z table)
Confidence interval : (p1 - p2) ± E
E =Zα/2 * √[(p1q1/n1) + (p2q2/n2)]
p1 = x1 /n1 =181/1205 = 0.1502
q1 = 1 - p1 = 1 -0.1502 = 0.8498
p2 = x2/n2 = 143/1097 = 0.1304
q2 = 1 - p2 = 1 -0.1304 = 0.8696
E = 1.96 * √(0.0001059 + 0.0001033)
E = 0.0283
p1 - p2 = 0.1502 - 0.1304 = 0.0198
Lower boundary = 0.0198 - 0.0283 = −0.0085
Upper boundary = 0.0198 + 0.0283 = 0.0481
(−0.0085 ; 0.0481)
-2(9 - x - 7)
= -2(2 - x)
= -4 + 2x
Answer:
-4 + 2x
720% because 1/5 is 20% and 7 is 700% so you add
