Answer:
the probability that a sample of the 35 exams will have a mean score of 518 or more is <em> 0.934 </em>or<em> 93.4%</em>.
Step-by-step explanation:
This is s z-test because we have been given a sample that is large (greater than 30) and also a standard deviation. The z-test compares sample results and normal distributions. Therefore, the z-statistic is:
(520 - 518) / (180/√35)
= 0.0657
Therefore, the probability is:
P(X ≥ 0.0657) = 1 - P(X < 0.0657)
where
- X is the value to be standardised
Thus,
P(X ≥ 0.0657) = 1 - (520 - 518) / (180/√35)
= 1 - 0.0657
= 0.934
Therefore, the probability that a sample of the 35 exams will have a mean score of 518 or more is <em>0.934 or 93.4%</em>.
Width of the rectangle is 9 units
Step-by-step explanation:
- Step 1: Let the width of the rectangle be x. Then the length = x - 3. Find dimensions of the rectangle if its area = 54 sq. units
Area of the rectangle = length × width
54 = x (x - 3)
54 = x² - 3x
x² - 3x - 54 = 0
x² + 6x - 9x - 54 = 0 (Using Product Sum rule to factorize)
x(x + 6) - 9(x + 6) = 0
(x + 6)(x - 9) = 0
x = -6, 9 (negative value is neglected)
x = 9 units
Answer:
Option A.
Step-by-step explanation:
The vector shown in the figure has components on the x axis and on the y axis.
If each small box on the draw represents a unit, it can be seen that the vector has a component of<u> length equal to 1 on the positive y-axis </u>and a length equal to 4 on the positive x-axis.
Look at the attached image
The sum of these two components results in the vector shown in the figure. Therefore the correct option is option A.
The length is equal to 1
This question is not complete
Complete Question
A boat sails 4km on a bearing of 038 degree and then 5km on a bearing of 067 degree.(a)how far is the boat from its starting point.(b) calculate the bearing of the boat from its starting point
Answer:
a)8.717km
b) 54.146°
Step-by-step explanation:
(a)how far is the boat from its starting point.
We solve this question using resultant vectors
= (Rcos θ, Rsinθ + Rcos θ, Rsinθ)
Where
Rcos θ = x
Rsinθ = y
= (4cos38,4sin38) + (5cos67,5sin67)
= (3.152, 2.4626) + (1.9536, 4.6025)
= (5.1056, 7.065)
x = 5.1056
y = 7.065
Distance = √x² + y²
= √(5.1056²+ 7.065²)
= √75.98137636
= √8.7167296826
Approximately = 8.717 km
Therefore, the boat is 8.717km its starting point.
(b)calculate the bearing of the boat from its starting point.
The bearing of the boat is calculated using
tan θ = y/x
tan θ = 7.065/5.1056
θ = arc tan (7.065/5.1056)
= 54.145828196°
θ ≈ 54.146°
Answer:
1)- Variable utilities cost per machine hour = 1.6 per machine hour
2)- Fixed cost = 1740
3)-Total cost on 1220 Machine hour will be
= 3692
Step-by-step explanation:
1) CALCULATE VARIABLE UTILITIES COST PER MACHINE HOUR :
Variable utilities cost per machine hour = Change in cost/high machine hour-low machine hour
=4076-3388/1460-1030
Variable utilities cost per machine hour = 1.6 per machine hour
2) Fixed cost = Total cost-variable cost
= 3388-(1030*1.6)
Fixed cost = 1740
3) Total cost on 1220 Machine hour will be (1220*1.6+1740) = 3692
