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Advocard [28]
3 years ago
10

7. David bought two types of cards. He bought x type of cards that cost $4 andy

Mathematics
1 answer:
PIT_PIT [208]3 years ago
7 0

Answer:

Step-by-step explanation:

x +  y = 22

22 cards = 26

5(4) +y(2) = 26

20+2y = 26

20-20 +2y = 26-20

2y =6

2y/2 = 6/2

y = 3

andy bought 3 cards

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Prove that in any triangle the length of a side is less than the half of the perimeter in statement reason format.
horrorfan [7]

Answer:

Proved

Step-by-step explanation:

I am going to pose c as the largest side in a random triangle

If so then remember that, by the triangle inequality, a + b > c. Let's start from there...

Statement:                         |                                  Reasoning:

1. a + b > c                                                             1. Triangle Inequality

2. a + b + c > c + c (adding c on both sides),      2. Algebra + Def. Of Perimeter

   a + b + c > 2c (simplified)

   Perimeter > 2c (definition of perimeter)

   c < 1/2 * Perimeter

3 0
3 years ago
A phone manufacturer wants to compete in the touch screen phone market. He understands that the lead product has a battery life
Tasya [4]

Answer:

(a) <em>H₀</em>: <em>μ</em> ≤ 10. vs. <em>Hₐ</em>: <em>μ</em> > 10.

(b) The test statistic value is 1.86.

(c) The critical value to test the phone manufacturer's claim is 1.301.

(d) The battery life of the new touch screen phone is not more than 10 hours.

Step-by-step explanation:

In this case we need to determine the significance of the claim made by the phone manufacturer, that the battery life of the new touch screen phone is more than twice as long as that of the leading product.

The information provided is:

\bar x=10.5\\s=1.8\\n=45

(a)

The hypothesis can be defined as follows:

<em>H₀</em>: The battery life of the new touch screen phone is not more than 10 hours, i.e. <em>μ</em> ≤ 10.

<em>Hₐ</em>: The battery life of the new touch screen phone is more than 10 hours, i.e. <em>μ</em> > 10.

(b)

As the population standard deviation is not provided, we will use a <em>t</em>-test for single mean.

Compute the test statistic value as follows:

 t=\frac{\bar x-\mu}{s/\sqrt{n}}=\frac{10.5-10}{1.8/\sqrt{45}}=1.86

The test statistic value is 1.86.

(c)

The significance level of the test is, <em>α</em> = 0.10.

The degrees of freedom will be:

df=n-1=45-1=44

Compute the critical value as follows:

t_{0.10, 44}=1.301

*Use a <em>t</em>-table for the value.

Thus, the critical value to test the phone manufacturer's claim is 1.301.

(d)

Decision rule:

If the test statistic value is less than the critical value then the null hypothesis will be rejected and vice-versa.

 t = 1.86 > t₀.₁₀, ₄₄ = 1.30

The calculated <em>t</em>-value of the test is more than the critical value.

The null hypothesis will not be rejected.

Thus, it can be concluded that the battery life of the new touch screen phone is not more than 10 hours.

6 0
3 years ago
Really easy question !!!!!!!<br> Linear Algebra
stiks02 [169]

Answer:

Okay thank you

Step-by-step explanation:

5 0
2 years ago
Read 2 more answers
Please help me please!!!
GenaCL600 [577]

Answer:

a is the answer

Step-by-step explanation:

because i said so

5 0
2 years ago
Read 2 more answers
Is 9/27 irrational number
kolbaska11 [484]
Yes because 27 divide by 9 is 3 and if you times 9 and 3 you will get 27
5 0
3 years ago
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