Answer: n = 14
Step-by-step explanation: margin of error = critical value × σ/√n
Where σ = population standard deviation = 1
n = sample size = ?
We are to construct a 99% confidence interval, hence the level of significance is 1%.
The critical value for 2 tailed test at 1% level of significance is gotten from a standard normal distribution table which is 2.58
Margin of error = 0.7
0.7 = 2.58×1/√n
0.7 = 2.58/√n
By cross multipying
0.7×√n = 2.58
By squaring both sides
0.7^2 × n = 2.58^2
0.49 × n = 6.6564
n = 6.6564/0.49
n = 14
Answer:
Step-by-step explanation:
In this particular case we have the following system of equations:
y
=
−
3
x
+
4
[
E
q
.
1
]
x
+
4
y
=
−
6
[
E
q
.
2
]
Substituting
[
E
q
.
1
]
in
[
E
q
.
2
]
:
x
+
4
(
−
3
x
+
4
)
=
−
6
Applying the distributive property on the left side:
x
−
12
x
+
16
=
−
6
Simplifying
:
−
11
x
=
−
22
Solving for
y
:
x
=
−
22
−
11
=
2
Substituting
x
=
2
in
[
E
q
.
1
]
:
y
=
−
3
(
2
)
+
4
=
−
2
Therefore
, the solutions are
x
=
2
and
y
=
−
2
48 develop a fault out of the total built which is 2400 therefore
48/2400
If needs to be simplified then 1/50
-3 (-5) = 15
two negatives= a positive
when a number is next to a number in brackets in means multiply.
Total amount = $80
Amount spent on Monday = 3/5 x 80 = $48
Amount remaining = $80 - $48 = $32
The money is spent over 5 days:
5 days = $32
1 day = $32 ÷ 5 = $6.40
Answer: She spent $6.40 on each of the 5 days.
