Tommorow I have maths exam can anyone help me please grade 9 cbse

The sum of three numbers is 18. If every number is a prime number, what are the three numbers?

sleet_krkn [62]

The three numbers are 2, 5, and 11.

The sum of 3 numbers is 18. 2 + 5 + 11 = 18

Since the problem states that every number is a prime number, then the number must be a natural number greater than 1 that has no positive divisors other than 1 and itself.

2 / 1 = 2 OR 2 / 2 = 1 These numbers are prime numbers because their divisors
5 / 1 = 5 OR 5 / 5 = 1 are 1 and itself.
11/1 = 11 OR 11/11 = 1

4 0

2 years ago

Read 2 more answers

How to find the perimeter of a semicircle

Elza [17]

Answer: $Formula: P=\frac{\pi d}{2}+d$

Step-by-step explanation:

$Formula: P=\frac{\pi d}{2}+d$

Where;

$P=perimeter\\\pi = pi (3.14)\\d= diameter\\$

5 0

3 years ago

A nationwide study of American homeowners revealed that 65% have one or more lawn mowers. A lawnequipment manufacturer, located

GenaCL600 [577]

Answer:

$z=\frac{0.684 -0.65}{\sqrt{\frac{0.65(1-0.65)}{497}}}=1.589$

$p_v =P(z>1.589)=0.056$

If we compare the p value obtained with the significance level assumed $\alpha=0.05$ we see that $p_v>\alpha$ so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, and we can said that at 5% of significance the proportion of homes in Omaha with one or more lawn mowers is not ignificantly higher than 0.65

Step-by-step explanation:

Data given and notation

n=497 represent the random sample taken

X=340 represent the homes in Omaha with one or more lawn mowers

$\hat p=\frac{340}{497}=0.684$ estimated proportion of homes in Omaha with one or more lawn mowers

$p_o=0.65$ is the value that we want to test

$\alpha$ represent the significance level

z would represent the statistic (variable of interest)

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

Concepts and formulas to use

We need to conduct a hypothesis in order to test the true proportion of homes in Omaha with one or more lawn mowers is higher than 0.65.:

Null hypothesis: $p\leq 0.65$

Alternative hypothesis: $p > 0.65$

When we conduct a proportion test we need to use the z statistic, and the is given by:

$z=\frac{\hat p -p_o}{\sqrt{\frac{p_o (1-p_o)}{n}}}$ (1)

The One-Sample Proportion Test is used to assess whether a population proportion $\hat p$ is significantly different from a hypothesized value $p_o$ .

Calculate the statistic

Since we have all the info requires we can replace in formula (1) like this:

$z=\frac{0.684 -0.65}{\sqrt{\frac{0.65(1-0.65)}{497}}}=1.589$

Statistical decision

It's important to refresh the p value method or p value approach . "This method is about determining "likely" or "unlikely" by determining the probability assuming the null hypothesis were true of observing a more extreme test statistic in the direction of the alternative hypothesis than the one observed". Or in other words is just a method to have an statistical decision to fail to reject or reject the null hypothesis.

The next step would be calculate the p value for this test.

Since is a right tailed test the p value would be:

$p_v =P(z>1.589)=0.056$

If we compare the p value obtained with the significance level assumed $\alpha=0.05$ we see that $p_v>\alpha$ so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, and we can said that at 5% of significance the proportion of homes in Omaha with one or more lawn mowers is not ignificantly higher than 0.65

7 0

2 years ago

This is a little difficult for me! Can someone explain?

ch4aika [34]

Answer:

We can write sin 21° as 1200 / x and also 0.36 so we can write:

1200 / x = 0.36

1200 = 0.36x

x = 1200 / 0.36

x ≈ 3333 ft

5 0

3 years ago

X∙5∙25∙4÷5, if x=813

Finger [1]

21,300 bc 813* 5=4,065 *25=101,625 *4=106,500 /5= 21,300

7 0

2 years ago