All categories

3 years ago

How to evaluate the expression 13 • 4

Mathematics

1 answer:

soldi70 [24.7K]3 years ago

5 0

Answer:

Step-by-step explanation:

Evaluting an expression basically means to multiply the numbers given.

In this certain question, we are just multiplying 13 by 4 which would give us the result of 52.

You might be interested in

A software engineer is creating a new computer software program. She wants to make sure that the crash rate is extremely low so

Soloha48 [4]

Answer:

a) the sample size is 400

b) 95% confidence Interval for p is ( 0.0286, 0.0714 )

Step-by-step explanation:

Given the data in the question;

sample size n = 400

x = 20

p = x / n = 20 / 400 = 0.05

q = 1 - p = 1 - 0.05 = 0.95

n = 400

Hence, the sample size is 400

b) 95% confidence Interval for p;

At 95% confidence interval,

significance level ∝ = 1 - 95% = 1 - 0.95 = 0.05

∝/2 = 0.05 / 2 = 0.025

so, Z critical Value ; $Z_{\alpha /2$ = 1.96 { from table }

So for Confidence Interval for p;

⇒ p' ± $Z_{\alpha /2$ √( p'q' / n )

we substitute

⇒ 0.05 ± 1.96√( (0.05 × 0.95 ) / 400 )

⇒ 0.05 ± 1.96√( 0.00011875 )

⇒ 0.05 ± 1.96 × 0.010897

⇒ 0.05 ± 0.021358

⇒ ( 0.05 - 0.021358 ), ( 0.05 + 0.021358 )

⇒ ( 0.0286, 0.0714 )

Therefore, 95% confidence Interval for p is ( 0.0286, 0.0714 )

8 0

3 years ago

Answer the question now

Brut [27]

Answer:

44, 3.5

11 x 4= 44

3.5 x 1 = 3.5

3 0

3 years ago

How much times can 6 go into 48

DENIUS [597]

6 can go into 48 8 times. How I figured out?
Start multiplying from a small number like
6×6= 36
6×7=42
6×8= 48
until you see your number 48, or a number that is lower that 48, but can not go any higher than 48.

6 0

3 years ago

A Pew Internet poll asked cell phone owners about how they used their cell phones. One question asked whether or not during the

EastWind [94]

Answer:

a) $\hat p=\frac{471}{1024}=0.460$

The standard error is given by:

$SE= \sqrt{\frac{\hat p(1-\hat p)}{n}}=\sqrt{\frac{0.460(1-0.460)}{1024}}=0.0156$

And the margin of error is given by:

$ME=z_{\alpha/2} \sqrt{\frac{\hat p(1-\hat p)}{n}}=1.96\sqrt{\frac{0.460(1-0.460)}{1024}}=0.0305$

b) The 99% confidence interval would be given by (0.429;0.491)

Step-by-step explanation:

A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".

The margin of error is the range of values below and above the sample statistic in a confidence interval.

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

The population proportion have the following distribution

$p \sim N(p,\sqrt{\frac{p(1-p)}{n}})$

Data given and notation

n=1024 represent the random sample taken

X=471 represent the people responded that they had used their cell phone while in a store within the last 30 days to call a friend or family member for advice about a purchase they were considering

$\hat p=\frac{471}{1024}=0.460$ estimated proportion of people responded that they had used their cell phone while in a store within the last 30 days to call a friend or family member for advice about a purchase they were considering

p= population proportion of people responded that they had used their cell phone while in a store within the last 30 days to call a friend or family member for advice about a purchase they were considering

Part a

The confidence interval would be given by this formula

$\hat p \pm z_{\alpha/2} \sqrt{\frac{\hat p(1-\hat p)}{n}}$

For the 95% confidence interval the value of $\alpha=1-0.95=0.05$ and $\alpha/2=0.025$ , with that value we can find the quantile required for the interval in the normal standard distribution.