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3 years ago

Ms. Williams wants to analyze the scores for the first unit test of her NC Math 1 class

Mathematics

2 answers:

marishachu [46]3 years ago

6 0

Answer:

Mean:79

Median:81

Standard deviation:15

Interquartile range:22

kondor19780726 [428]3 years ago

6 0

Mean (aka average)-79.8928

add all the numbers together and divide by how many numbers there are

sum of terms-2237

number of terms-28

Median- 81

I do it this way-

order the numbers from least to greatest

cross off the front number and back number until you are left with a middle

in this case there were 2

80 and 82

the average of those two is 81

Standard Deviation-15.37237

Interquartile Range-22.5

25th percentile-71

50th percentile-81

75th percentile-93

You might be interested in

My Homework Mr Thompson please help!!

Nady [450]

Answers:

C) Factored form
C) Standard form
D) The y intercept is -8
B) Two solutions: x = -5 or x = 5
B) Apply square root to both sides

=========================================

Explanations:

For problems 1 and 2, there's not much to say other than you'll just have to memorize those terms. Standard form is ax^2+bx+c in general. The exponents count down 2,1,0. Factored form is where we have two or more factors multiplying with each other. Think of something like 21 = 7*3 showing that 7 and 3 are factors of 21.
For problem 3, the y intercept is the last value. It's the constant value. Plug in x = 0 and you'll get y = -8 as a result. The y intercept always occurs when x = 0.
In problem 4, we apply the square root to both sides to get x = -5 or x = 5. The plus or minus is needed. This is because (-5)^2 = 25.
In problem 5, we apply the square root to both sides to undo the squaring operation.

4 0

3 years ago

| 9. The distance between Town A and Town B was 108 km. A car and a van left Town A at 12 00 for Town B. On reaching Town B, the

Westkost [7]

Answer:

a) Time until both vehicles meet is 1.5 hours after starting at noon. That makes it 1:30PM.

b) Average speed of car is 84 km/h

Step-by-step explanation:

A -----------------------z------------B

Left Speed(km/h) Time

Car: 12PM X

Van: 12PM 60

Car/Van

DistanceCar AB + z

DistanceVan Az

Ratio: (AB+z)/Az = 7/5

Time until both meet = T (in hours)

Distance Car: xT

Distance Van: 60T

====

xT = AB + z

60T = Az

---

(xT/60T)= (7/5)

x = 60(7/5)

x = 84 km/h

=====

Time for car to reach B is: time (hr) = 108 km/(84 km/h)

time = 1.286 hours

Distance for at 1.289 hours is: distance (km) = (60 km/h)*(1.286 h)

distance = 77.14 km

At 1.286 hours, the car reverses direction. The van is (108 km - 77.14 km) or 30.86 km away.

Add the distances travelled by both vehicles after the car reverses direction at 1.286 hours. The sum will be 30.86 km when they meet, at time of T.

Car Distance + Van Distance = 30.86 km

T(84 km/h) + t(60 km)

They meet when they are 0 km apart, which can be modeled with the following equation:

Van travel Distance - Car Travel Distance = 0 starting at 1.286 hr.

Let t be the time after 1.286 hours that both vehicles meet/collide.

t*(60 km/h) + t(84 km/h) = 30.86 km

t(60+84) = 30.86 km

t(144 km/h) = 30.86 km

t = 0.2143 hr

Total time until the car and van meet is 1.286 hr + 0.2143 hr for a total of 1.50 hours.

=================

a) Time until both vehicles meet is 1.5 hours after starting at noon. That makes it 1:30PM.

b) Average speed of car is 84 km/h

==============

CHECK

Is the ratio of the distance travelled by the car and the van until they meet in the ratio of 7/5?

Car distance is (1.5 hr)(84 km/h) = 126 km

Van distance is (1.5 hr)(60 km/h) = 90.0 km

Ratio is 126/90 or 1.4

Ratio of 7/5 is 1.4

YES

3 0

2 years ago

Which statements are true? (look at picture)

Makovka662 [10]

Answer:

D is true, E is true, F is true

Step-by-step explanation:

Hello,

n is an odd number it means that n = 2a+1 where a is integer

$n^2-1=(2a+1)^2-1=4a^2+4a+1-1=4a(a+1)$

this is not an odd number

$n(n-1)=(2a+1)2a$

this is not an odd number

$(n-1)^2=(2a+1-1)^2=4a^2$

this is not an odd number

$n^2+2=(2a+1)^2+2=4a^2+4a+1+2=4a^2+4a+3= 2(2a^2+2a+1)+1$

so this is an odd number

$n(n-2)=(2a+1)(2a-1)=4a^2-1=4a^2-2+1=2(2a^2-1)+1$

so this is an odd number

$(n-2)^2=(2a+1-2)^2=(2a-1)^2=4a^2-4a+1 = 2(2a^2-2a)+1$

this is an odd number

hope this helps

7 0

3 years ago

The cost of hiring a taxi consists of a fixed cost of $3 plus $0.5 per kilometer distance travelled. Write an expression in term

irinina [24]

Answer:

The required expression is:

y = 0.5x + 3

Please check the attached graph too.

Step-by-step explanation:

The slope-intercept form of the linear or line function

$y = mx+b$

where

m is the rate of change or slope

b is the y-intercept

In our case,

The cost of hiring a taxi consists of a fixed cost of $3. It means the fixed cost of $3 is the initial condition.

Thus, the y-intercept b = 3

It is stated that the cost of per kilometer distance = $0.5

Thus, the rate of change or slope m = 0.5

As y represents the cost and x represents the number of kilometers.

so substituting m = 0.5 and b = 3 in the slope-intercept form of the linear or line function

y = mx+b

y = 0.5x + 3

Thus, the required expression is:

y = 0.5x + 3

Please check the attached graph too.

5 0

3 years ago

"My new phone cost a fortune,"said Amy. " Mine costs twice as much," said Jill. If together, the two phones cost $575.25, how mu

Naddik [55]

Answer:

Cost of Amy's Phone= $191.75

Cost of Jill's phone = $191.75*2= $383.5

Step-by-step explanation:

let Amy's phone cost be A

Jill's phone cost = 2A

A/Q-

A +2A = $575.25

3A= $575.25

A=$575.25/3

A= $191.75

then,

Cost of Amy's Phone= $191.75

Cost of Jill's phone= $191.75*2= $383.5

3 0

3 years ago