All categories

3 years ago

A short necklace has 32 gold beads and 8 black beads.

Mathematics

1 answer:

joja [24]3 years ago

3 0

Answer:

12 black beads

Step-by-step explanation:

Given the ration of gold beads to black beads on the short necklace:

$\frac{gold}{black}=\frac{32}{8}=\frac{4}{1}$

Since the ratio of 4:1 has 5 total parts, you can take the total amount of beads in the long necklace and divide by 5:

60 ÷ 5 = 12

12 beads represents 1 part of the ratio, so that would be the number of black beads. To check, multiply 12 by 4: 12 x 4 = 48, and set up a ratio:

48: 12 = 4: 1

You might be interested in

Two California landmarks, Mt Whitney and Death Valley, are the highest and lowest points in lower 48 states. The difference in e

Varvara68 [4.7K]

We can find out he answer to the question by using the information given.
Since we know that Death Valley is the lower of the two spots, we can assume that we can add the difference in elevation to Death Valley to get the elevation of Mt Whitney.
-86+4,504=4,418
Th elevation of Mt Whitney is 4,418 meters above ground.
Hope this helps!

5 0

3 years ago

Let f(x) = x2 − 2x − 3. The secant line through (2, f(2)) and (2 + h, f(2 + h)) for f(x) has slope h + 2. Use this formula to co

Mkey [24]

Answer:

a) slope of secant line = 3

b) slope of tangent line = 2

Step-by-step explanation:

Given:

- The function:

f(x) = x^2 -2*x - 3

- The slope for f(x) @ x = 2 is:

slope = h + 2

Find:

a) The slope of the secant line through (2, f(2)) and (3, f(3))

b) The slope of the tangent line at x = 2

Solution:

- Since we are given the slope of the line computed via secant method. All we need to do is evaluate the slope given for respective question.

- The slope of secant line between points ( 2 , f(2) ) and ( 3 , f(3) ) is:

slope = h + 2

Where, h is the step size between two points. h = 3 - 2 = 1

slope = 1 + 2 = 3

Hence, the slope of the secant is 3.

- The slope of tangent line @ points ( 2 , f(2) ) is:

slope = Lim _ h-->0 (h + 2)

Where, h step size is reduced to infinitesimal small number. Hence, h = 0

slope = 0 + 2 = 2

Hence, the slope of the tangent is 2.

5 0

4 years ago

Y+3=−4(x+7)<br> what is the slope>

Wewaii [24]

Answer:

......Im pretty sure its -4

7 0

3 years ago

Read 2 more answers

3.5x-1=-1/2(-7x+2) I know how to solve it which is

Dafna11 [192]

3.5x - 1 = -1/2(-7x + 2)
3.5x - 1 = 7/2x - 1 By virtue of the distributive property
7/2 = 3.5, so there is no solution. The statement is true for any value of x.

Essentially it boils down to -1 = -1, which is always true.

3 0

3 years ago

2. A particular resource class must perform at a level consistent with the rest of the school to avoid being discontinued. On th

Natali5045456 [20]

Answer:

$t=\frac{71.86-78}{\frac{17.52}{\sqrt{14}}}=-1.311$

$p_v =P(t_{13}$

If we compare the p value and a significance level assumed for example $\alpha=0.05$ we see that $p_v>\alpha$ so we can conclude that we FAIL to reject the null hypothesis, and the actual true mean for the scores is NOT significant less than 78.

Step-by-step explanation:

Data given and notation

$\bar X=71.86$ represent the sample mean

$s=17.52$ represent the standard deviation for the sample

$n=14$ sample size

$\mu_o =78$ represent the value that we want to test

$\alpha$ represent the significance level for the hypothesis test.

t would represent the statistic (variable of interest)

$p_v$ represent the p value for the test (variable of interest)

State the null and alternative hypotheses.

We need to conduct a hypothesis in order to determine if the mean is less than 78, the system of hypothesis would be:

Null hypothesis: $\mu \geq 78$

Alternative hypothesis: $\mu < 78$

We don't know the population deviation, so for this case is better apply a t test to compare the actual mean to the reference value, and the statistic is given by:

$t=\frac{\bar X-\mu_o}{\frac{s}{\sqrt{n}}}$ (1)

t-test: "Is used to compare group means. Is one of the most common tests and is used to determine if the mean is (higher, less or not equal) to an specified value".

Calculate the statistic

We can replace in formula (1) the info given like this:

$t=\frac{71.86-78}{\frac{17.52}{\sqrt{14}}}=-1.311$

Calculate the P-value

First we need to find the degrees of freedom given by:

$df=n-1=14-1=13$

Since is a one-side left tailed test the p value would be:

$p_v =P(t_{13}$

Conclusion

3 0

3 years ago