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Rudik [331]
3 years ago
5

Lucy wants to be exempt from her semester exam. In order for that to happen, she has to average an 85 over 3 test grades. Her fi

rst 2 test grades were 81 and 86. What does Lucy need to make on her third test in order to have an exact average of 85 and be exempt from her exam?
Mathematics
1 answer:
anastassius [24]3 years ago
8 0

Answer:

<em>Grades to be scored in 3rd exam = 88</em>

Step-by-step explanation:

Given that average of 3 numbers is 85.

First two numbers are 81 and 86.

To find:

3rd number so that average is 85

Solution:

Let the third number = x

Formula for average is:

Average = \dfrac{Sum\ of\ numbers}{Total\ count\ of\ numbers}

Here, sum of numbers = 81+86+x =167+x

Total count of numbers = 3

85 = \dfrac{167+x}{3}\\\Rightarrow x=255-167\\\Rightarrow \bold{x=88}

<em>Grades to be scored in 3rd exam = 88</em>

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An employer with 500 employees gives out gives out 120 surveys but receives only 90 surveys completed by the employees. What are
leva [86]

Answer:

Population 120 given the survey, sample 90 who answered the survey.

Step-by-step explanation:

The entire amount of employees who even received the surveys at all was 120. Because the total number was 120, 120 is the population.

Only 90 out of 120 surveys were received, so 90 is the sample because it is part of 120.

Hope this helps :)

6 0
3 years ago
A line intersects the points (6, -12) and (15, -3). What is the slope intercept equation for this line?
Korolek [52]
Let's say that the unknown value here is c. Although we are given two points on the line, it is only necessary to use one as there is only one unknown value, so let's say we choose the point (6, -12) and substitute this into the equation:

-12 = 1(6) - c
-12 - 6 = -c
-18 = -c
c = 18

Thus the equation for the line is y = 1x - 18
8 0
3 years ago
6. A factory has two types of machines.
Pie

210 pieces

Step-by-step explanation:

First, you need to figure out how many pieces a single machine can cut in a minute, so you need to divide 105 by 3, which gets you 35 pieces per minute.

Next, since we know there are 6 machines, and one machine canncut 35 pieces per minute, we can the figure out how many pieces all 6 cutting machines can cut in 1 minute. You would do this by making an equation such as this:

35 \times 6 = x

The x represents the total number of pieces cut by all 6 machines in one minute.

Next, since we now have an equation, we can go ahead and solve it. We would multiply 35 by 6, which would get us 210 pieces per minute that can be cut by all six machines

8 0
3 years ago
Read 2 more answers
What is the slope of the line passing through<br> points (6, -1) and (1,8)?
Fynjy0 [20]

Answer:

-1.8

Step-by-step explanation:

m= y2 - y2over x2 - x1

m= -1 - 8 over 1 - 6 = -1.8

m= -1.8

7 0
3 years ago
Mr jones is planning to pant grass and place afence in a small area for his dog. The rectagular dimension are 12×15 feet. The gr
goldenfox [79]

Answer:

A) The total feet needed for the fence total perimeter is 54 feet

B) The total cost of fence is $432

C) The square feet of grass needed foe the total area is 180 square feet

D) The total cost of the project is $572

Step-by-step explanation:

Given as :

The dimension of rectangular field

Length of rectangular field = L = 12 feet

width of rectangular field = w = 15 feet

The cost of grass per square foot = 50 cents = $0.5    ( ∵ 1 cents = $0.01 )

The cost of small fence = $8 per linear foot

Now, According to question

A ) Let The total feet needed for the fence total perimeter = A feet

∵ Perimeter of rectangular field = 2 × Length + 2 × width

Or, A = 2 × L + 2 × w

Or, A = 2 × 12 feet + 2 × 15 feet

Or, A = 24 feet + 30 feet

∴ A = 54 feet

So, The total feet needed for the fence total perimeter = A = 54 feet

B ) Let The total cost of fence = $B

So, The total cost of fence = The cost of small fence × perimeter of fence

i.e B = $8 × 54 feet

∴ B = $432

So,The total cost of fence = B = $432

C) Let the square feet of grass needed foe the total area = C square feet

∵The Area of rectangular fence = Length × width

Or, The square feet of grass needed foe the total area = Area of rectangular fence = L × w

i.e C = 12 feet × 15 feet

Or, C = 180 feet²

So,The square feet of grass needed foe the total area = C = 180 square feet

D) Let The total cost of grass = $D

∵ The cost of grass per square foot = $0.5

So,Total cost of grass = $0.5 × Area of fence

i.e D = $0.5 ×  180 feet²

Or, D = $90

So, The Total cost of grass = D = $90

E) Let the total cost of the project = $E

∵Mr. Jones spend additional $50 for tools

So, The total cost of the project =  money spent on tools + total cost of fence + Total cost of grass

i.e E = $50 + B + D

Or, E = $50 + $432 + $90

∴ E = $572

So, The total cost of the project = E = $572

Hence,

A) The total feet needed for the fence total perimeter is 54 feet

B) The total cost of fence is $432

C) The square feet of grass needed foe the total area is 180 square feet

D) The total cost of the project is $572  Answer

3 0
3 years ago
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