All categories

3 years ago

The sum of the ages of Nicole and Rachel is 30. Currently Nicole is four years older than Rachel. How old is Rachel?

Mathematics

2 answers:

PSYCHO15rus [73]3 years ago

7 0

Since Nicole is 17, and Rachel is four years younger, her age is 13. This answer makes sense because 17+13=30.

Lunna [17]3 years ago

3 0

Rachel is 13. since Nicole is 17.
13+17=30

You might be interested in

What is the equation of the line that is parallel to y=6x−1 and passes through the point (−3,4)?

BabaBlast [244]

Answer: y = 6x + 22

Step-by-step explanation:

Parallel lines have same slope. So, a line parallel to y = 6x − 1 is y = 6x + c.

Now to find c, put (-3,4) to this equation since the line passes through the point.

4 = 6 × -3 + c

4 = -18 + c

4 + 18 = c

c = 22

So, equation is y = 6x + 22

3 0

3 years ago

Read 2 more answers

What is this graphs slope?

Ksivusya [100]

Answer:

slope = -4

Step-by-step explanation:

Given the following points on the graph: (-1, 4) (1, -4)

Let (x1, y1) = (-1, 4)

(x2, y2) = (1, -4)

Use the following slope formula:

$m = \frac{y2 - y1}{x2 - x1}$

$m = \frac{-4 - 4}{1 - (-1)} = \frac{-8}{1 + 1} = \frac{-8}{2} = -4$

Therefore, the slope of the line is -4

3 0

3 years ago

Here someone help me is this correct or no someone reported me saying it was wrong

Neko [114]

$-2^{4} = 16$

You're right.

8 0

3 years ago

Read 2 more answers

An arc is 6.5 cm long and it subtends a central angle of 45 degrees. Find the radius of the circle.

Orlov [11]

Arc length = radius * central angle (measured in radians)
There are 57.2957795131 degrees per radian so
45 degrees = (45 / 57.2957795131) = 0.7853981634 radians 
radius = arc length / central angle (radians)
radius = 6.5 / 0.7853981634 radians = 8.2760570408 cm

http://www.1728.org/radians.htm

8 0

3 years ago

Lightbulbs of a certain type are advertised as having an average lifetime of 750 hours. The price of these bulbs is very favorab

Katyanochek1 [597]

Answer:

(a) Customer will not purchase the light bulbs at significance level of 0.05

(b) Customer will purchase the light bulbs at significance level of 0.01 .

Step-by-step explanation:

We are given that Light bulbs of a certain type are advertised as having an average lifetime of 750 hours. A random sample of 50 bulbs was selected, and the following information obtained:

Average lifetime = 738.44 hours and a standard deviation of lifetimes = 38.2 hours.

Let Null hypothesis, $H_0$ : $\mu$ = 750 {means that the true average lifetime is same as what is advertised}

Alternate Hypothesis, $H_1$ : $\mu$ < 750 {means that the true average lifetime is smaller than what is advertised}

Now, the test statistics is given by;

T.S. = $\frac{Xbar-\mu}{\frac{s}{\sqrt{n} } }$ ~ $t_n_-_1$

where, X bar = sample mean = 738.44 hours

s = sample standard deviation = 38.2 hours

n = sample size = 50

So, test statistics = $\frac{738.44-750}{\frac{38.2}{\sqrt{50} } }$ ~ $t_4_9$

= -2.14

(a) Now, at 5% significance level, t table gives critical value of -1.6768 at 49 degree of freedom. Since our test statistics is less than the critical value of t, so which means our test statistics will lie in the rejection region and we have sufficient evidence to reject null hypothesis.

Therefore, we conclude that the true average lifetime is smaller than what is advertised and so consumer will not purchase the light bulbs.

(b) Now, at 1% significance level, t table gives critical value of -2.405 at 49 degree of freedom. Since our test statistics is higher than the critical value of t, so which means our test statistics will not lie in the rejection region and we have insufficient evidence to reject null hypothesis.

Therefore, we conclude that the true average lifetime is same as what it has been advertised and so consumer will purchase the light bulbs.

6 0

3 years ago