Answer:(a) margin error = 2.4%
(b) The margin error gives the measure in percentage of how the population parameter determined differ from the real population statistics or value.
(c) in 90% of the samples of teens in the country, the percent who go online several times a day will be within 50.6% and 55.4%. of the estimated 100%
Step-by-step explanation:
Using the proportion formulae
Margin error = z √p(1-p)/n
n= 1170, p = 53% = 0.53, 1-p = 0.47
and the z value at 90% C.I = 1.645
M error= 1.645 √0.53×0.47/1170
Margin error = 0.024 = 0.024 ×100
Margin error = 2.4%
53 - 2.4 = 50.6% and 53 + 2.4 = 55.4%
In other words 90% of the time: the number of teens who go online several time a day will be between 50.6 and 55.4%.
Answer:
£83.70
Step-by-step explanation:
→ First step is to find the amount of hours it takes for one builder
We know it takes 5 builders 
hours so 1 builder would take 5 × which is 
hours so it takes one builder 17.5 hours to builder a wall
→ Now we know how long one work takes we need to find out the time for 2 builders
1 builder = 17.5 hours
2 builders = 17.5 ÷ 2 = 8.75 hours
So 2 builders take 8.75 hours
→ We know that each builder is paid £9.30 for each or part hour they work so
9.30 hourly pay rate × 9 hours work of work = £83.70
Each worker will be paid £83.70
4x4=16 9x(-6)=-54 16+(-54)=-38 -7x-38=266
The min or max of a parabola/quadratic function is the vertex
for
y=a(x-h)²+k
the vertex is (h,k)
so
vertex/min is at (-1,2)
h=-1
k=2
y=a(x-(-1))²+2
y=a(x+1)²+2
find a
given, (2,20) is on the graph
20=a(2+1)²+2
20=a(3)²+2
20=9a+2
minus 2 both sides
18=9a
divide by 9
2=a
y=2(x+1)²+2 is da equation
3rd one
f(x)=2(x+1)²+2
Answer:
0.8
Step-by-step explanation:
E is .5 units from 0 and 0 is .3 units from w. .5+.3=.8 units
