All categories

3 years ago

If x is a rational number, then x + 12 could NOT be:

Mathematics

1 answer:

aalyn [17]3 years ago

5 0

Step-by-step explanation:

$x + 12 = 0$

$x = - 12$

hope it help you.

You might be interested in

Equation of slope? can it go both ways?

liraira [26]

Answer:

yes

Step-by-step explanation:

6 0

3 years ago

What is the value of c so that y+x^2+9x+c is a perfect square triangle?

Alona [7]

<span>x^2 - 9x + c
=x^2 - 2(x)(9/2) + (9/2)^2 is a perfect square
Therefore b = (9/2)^2 = 81/4
Ans: 81/4 </span>

4 0

3 years ago

In ΔRST, the measure of ∠T=90°, the measure of ∠S=67°, and RS = 6.2 feet. Find the length of TR to the nearest tenth of a foot.

NeX [460]

Answer:

5.7 feet

Step-by-step explanation:

3 0

3 years ago

jonathan sold his guitar for $20 and 6 baseball at the garage sale. he charged $38. What was the cost of each baseball?

evablogger [386]

The cost of each baseball was $3

5 0

3 years ago

The Fish and Game Department stocked a lake with fish in the following proportions: 30% catfish, 15% bass, 40% bluegill, and 15%

vagabundo [1.1K]

Answer:

1) $\chi^2 =\frac{(112-150)^2}{150}+\frac{(95-75)^2}{75}+\frac{(210-200)^2}{200}+\frac{(83-75)^2}{75}=16.313$

2) $p_v =P(\chi^2_{3}>16.313)=0.000978$

And we got the same decision reject the null hypothesis at 5% of significance.

Step-by-step explanation:

Previous concepts

The Chi-Square test of independence is used "to determine if there is a significant relationship between two nominal (categorical) variables". And is defined with the following statistic:

$\chi^2 =\sum_{i=1}^n \frac{(O-E)^2}{E}$

Where O rpresent the observed values and E the expected values.

State the null and alternative hypothesis

Null hypothesis: The distribution is 30% catfish, 15% bass, 40% bluegill, and 15% pike

Alternative hypothesis: The distribution is NOT 30% catfish, 15% bass, 40% bluegill, and 15% pike

The observed values are given by the table given:

Catfish =112, BAss = 95, Bluegill=210, Pike=83

Calculate the expected values

In order to calculate the expected values we can use the following formula for each cell of the table

$E = \% Grand total$

$E_{Catfish}=500*0.3=150$

$E_{Bass}=500*0.15=75$

$E_{Bluegill}=500*0.4=200$

$E_{Pike}=500*0.15=75$

Part 1: Calculate the statistic

$\chi^2 =\frac{(112-150)^2}{150}+\frac{(95-75)^2}{75}+\frac{(210-200)^2}{200}+\frac{(83-75)^2}{75}=16.313$

$\chi^2 =16.313$

Calculate the critical value

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

$df= (categories-1)=(4-1)= 3$

Since the confidence provided is 95% the significance would be $\alpha=1-0.95=0.05$ and we can find the critical value with the following excel code: "=CHISQ.INV(0.95,3)", and our critical value would be $\chi^2_{crit}=7.815$

We can calculate also the p value:

$p_v =P(\chi^2_{3}>16.313)=0.000978$

And we got the same decision reject the null hypothesis at 5% of significance.

5 0

3 years ago