To subtract 105 ? 73 using mental math, Sabine subtracted 105 ? 75 and got 30. What should she do next?

-5x + 32 = 47 What is the answer to the equation

SOVA2 [1]

Answer:

x = -3

Step-by-step explanation:

-5x + 32 = 47

-5x + 32 - 32 = 47 - 32

-5x = 15

-5x / -5 = 15 / -5

x = -3

7 0

4 years ago

Read 2 more answers

A college student is interested in investigating the TV-watching habits of her classmates and surveys 20 people on the number of

Alla [95]

Answer:

80% confidence interval of the true average number of hours of TV watched per week is [8.28 hours, 11.02 hours].

Step-by-step explanation:

We are given that a college student is interested in investigating the TV-watching habits of her classmates and surveys 20 people on the number of hours they watch per week. The results are provided below;

Hours of TV per week (X): 6, 14, 13, 6, 16, 10, 19, 4, 5, 5, 18, 8, 7, 14, 8, 8, 9, 12, 6, 5.

Firstly, the Pivotal quantity for 80% confidence interval for the true average is given by;

P.Q. = $\frac{\bar X-\mu}{\frac{s}{\sqrt{n} } }$ ~ $t_n_-_1$

where, $\bar X$ = sample mean number of hours of TV watched per week = $\frac{\sum X}{n}$ = 9.65

s = sample standard deviation = $\sqrt{\frac{\sum (X -\bar X)^{2} }{n-1} }$ = 4.61

n = sample of people = 20

$\mu$ = true average number of hours of TV watched per week

Here for constructing 80% confidence interval we have used One-sample t-test statistics as we don't know about population standard deviation.

So, 80% confidence interval for the true average, $\mu$ is ;

P(-1.33 < $t_1_9$ < 1.33) = 0.80 {As the critical value of t at 19 degrees of

freedom are -1.33 & 1.33 with P = 10%}

P(-1.33 < $\frac{\bar X-\mu}{\frac{s}{\sqrt{n} } }$ < 1.33) = 0.80

P( $-1.33 \times {\frac{s}{\sqrt{n} } }$ < ${\bar X-\mu}$ < $1.33 \times {\frac{s}{\sqrt{n} } }$ ) = 0.80

P( $\bar X-1.33 \times {\frac{s}{\sqrt{n} } }$ < $\mu$ < $\bar X+1.33 \times {\frac{s}{\sqrt{n} } }$ ) = 0.80

80% confidence interval for $\mu$ = [ $\bar X-1.33 \times {\frac{s}{\sqrt{n} } }$ , $\bar X+1.33 \times {\frac{s}{\sqrt{n} } }$ ]

= [ $9.65-1.33 \times {\frac{4.61}{\sqrt{20} } }$ , $9.65+1.33 \times {\frac{4.61}{\sqrt{20} } }$ ]

= [8.28 hours, 11.02 hours]

Therefore, 80% confidence interval of the true average number of hours of TV watched per week is [8.28 hours, 11.02 hours].

7 0

3 years ago

A linear function that represents the number of animals adopted from the shelter is compared to a different linear function that

bazaltina [42]

Answer:point slope form

y-y1=m(x-x1)

slope-intercept form

y=mx+b

slope formula

y2-y1/x2-x1

slope of line passing through (3.29,-9.19) & (3.29,4.72)

UNDEFINED

line perpendicular to y=3x-7 & passes through (3,5)

y-5 = -1/3(x-3)

slope of perpendicular lines

negative reciprocals (flip and change signs)

m --> -1/m

covering up method

only used with standard form

-4x + 7y = 56 Find x & y intercepts of equation

x = (-14,0) y = (0,8)

Terry is skiing down a steep hill. Terry's elevation E(t)

in feet after t seconds is given by E(t) = 2000 − 90t.

Write a complete sentence describing Terry's starting elevation and how it is changing over time.

Terry starts at an elevation of 2000 feet and descends at 90 feet per second.

If the graphs of two linear functions are perpendicular, describe the relationship between the slopes and the y-intercepts.

slope: negative reciprocals of one another.

y-intercept: There is no relationship.

Step-by-step explanation:

6 0

3 years ago

Abril and Alanis put some money into their money boxes every week. The amounts of money (y), in dollars, in their money boxes af

AnnZ [28]

Answer:

A. 3 weeks, $160

Step-by-step explanation:

If the value of y is same for both then we have equal right sides of equations

50x + 10 = 30x + 70

Solve this for x

50x - 30x = 70 - 10
20x = 60
x = 60/20
x = 3

Find the value of y

y = 50*3 + 10 = 150 + 10 = 160

Correct choice is A

8 0

2 years ago

What is the value of the digit in the ten thousands place in the number 67,868 ?

Veseljchak [2.6K]

9514 1404 393

Answer:

60,000

Step-by-step explanation:

To find your answer, set all other digits to zero.

60,000

is the value of the digit 6 in the 10 thousands place.

8 0

3 years ago