Answer:
C.I = 0.7608 ≤ p ≤ 0.8392
Step-by-step explanation:
Given that:
Let consider a random sample n = 400 candidates where 320 residents indicated that they voted for Obama
probability 
= 0.8
Level of significance ∝ = 100 -95%
= 5%
= 0.05
The objective is to develop a 95% confidence interval estimate for the proportion of all Boston residents who voted for Obama.
The confidence internal can be computed as:

where;
=
= 1.960
SO;






= 0.8 - 0.0392 OR 0.8 + 0.0392
= 0.7608 OR 0.8392
Thus; C.I = 0.7608 ≤ p ≤ 0.8392
Answer:
$9.50h, $(9.50h +2.20rh)
Step-by-step explanation:
Every hour ----- $9.50
h hours ----- h ×$9.50
Amount of money Mr Smith earns in h hours
= $9.50h
If he fixes a watch per hour, additional income= $2.20h
If he fixes r watches per hour, additional income= $2.20rh
Total income
= $(9.50h +2.20rh)
<span>740,679,835 km i hope this helps you
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