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1 year ago

Which product is positive?

Mathematics

2 answers:

Virty [35]1 year ago

4 0

Answer:

(Negative two-fifths) (Negative StartFraction 8 over 9 EndFraction) (one-third) (StartFraction 2 over 7 EndFraction)

Step-by-step explanation:

(Negative two-fifths) (Negative StartFraction 8 over 9 EndFraction) (one-third) (StartFraction 2 over 7 EndFraction) = (-2/5)(-8/9)(1/3)(2/7)

Let's take the fraction and eliminate the negative sign because negative multiply negative= positive

(-2/5)(-8/9)(1/3)(2/7)= 32/945

elena-14-01-66 [18.8K]1 year ago

4 0

Answer:

Step-by-step explanation:

two negatives equals a positive

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Please answer this I really need help, Ariel spent a total of $3.42 buying dried apricots from the bulk bins, which were on sale

Kamila [148]

Answer:

1.2 lbs

Step-by-step explanation:

This problem is set up so that the total price is proportional to the price per pound, so to find the proportion you would divide the total cost by the cost per pound. 3.42/2.85 = 1.2, so the answer is 1.2 pounds.

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1 year ago

A hexagonal pyramid is cut by a plane as shown in the diagram. What is the shape of the resulting cross section? see diagram

Alenkasestr [34]

From the diagram you can see that plane cuts each lateral face of hexagonal pyramid and do not cut the base. A hexagonal pyramid has six lateral faces. The intersection of each of these lateral faces with given cutting plane is segment. The figure which consists of these segments is hexagon. This hexagon is not the same as base and even is not similar to the base because the cutting plane is not parallel to the base.

Answer: resulting cross section is a hexagon, correct choice is option 4.

9 0

2 years ago

Read 2 more answers

Let the following sample of 8 observations be drawn from a normal population with unknown mean and standard deviation: 22, 18, 1

BigorU [14]

Answer:

a: Sample mean: 20, Sample standard deviation: 1.732

b: 19.13 <µ < 20.87

c: 18.84< µ < 21.16

d: as the confidence level increases, the interval becomes wider

Step-by-step explanation:

a: Sample mean is found by adding up all the individual values of the sample, then dividing by the total number of values in the sample.

Sample standard deviation is the square root of the variance

See the first attached photo for the calculations of these values.

We need to create a 80% confidence interval for the population. Since n < 30, we will use a t-value with degree of freedom of 7 (the degree of freedom is always one less than the sample size.

Look for the column on the t-distribution chart that has "area in two tails" of 0.20 (80%), and row 7 (degree of freedom)

The t-value is 1.415

See the second attached photo for the construction of the confidence interval

We need to create a 90% confidence interval for the population. Since n < 30, we will use a t-value with degree of freedom of 7 (the degree of freedom is always one less than the sample size.

Look for the column on the t-distribution chart that has "area in two tails" of 0.10 (90%), and row 7 (degree of freedom)

The t-value is 1.895

See the third attached photo for the construction of the confidence interval

3 0

2 years ago

On a rectangular soccer field, Sang is standing on the goal line 20 yards from the corner post. Jazmin is standing 99 yards from

Anna007 [38]

Okay, so Sang is standing 20 yards away from one corner, and Jazmin is standing 99 yards away from the same corner. If this is a rectangle (I like visuals, so I'll use them to explain), then:

99ft
A ------------------------- B
   |    |
20 ft |    |
   |    |
C -------------------------- D

The question is asking you to solve for the diagonal line between points C and B. If you imagine a line there, you actually have the rectangle split into two triangles. So if you have triangle ABC, side CB would be the longest line, or the hypotenuse. That means you can use the Pythagorean Theorem to solve the problem.

A^2 + B^2 = C^2
99^2 + 20^2 = C^2
9,801 + 400 = C^2
10,201 = C^2

Now you solve for the square root of 10,201 to get C.

sqr (10,201) = C
C = 101 yards

3 0

2 years ago

Consider a disease whose presence can be identified by carrying out a blood test. Let p denote the probability that a randomly s

barxatty [35]

Answer:

0 tests

Yes, this procedure is better on the average than testing everyone, it makes it less cumbersome.

Step-by-step explanation:

Given the information:

Let P be the probability that a randomly selected individual has the disease = 0.1. N individuals are randomly selected, thereafter, blood samples of each person would be tested after combining all specimens. Should in case one person has the disease then it yields a positive result and test should be set for each person.

Let Y be number tests

For n = 3 there are two possibilities. If no one has the disease then the value is 1 otherwise the value is 4, here P = 0.1

Therefore, for Y = 1

P(Y-1) = P(no one has disease)

= 0.9³

= 0.729

If Y = 4

P(Y-4) = 1-P(y = 1)

= 1 - 0.729 = 0.271

The expected number of tests using this formular gives

E(Y) = 1×0.729 + 4×0.271

E(Y) = 0

4 0

2 years ago