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3 years ago

Help plz:)))I’ll mark u Brainliest

Mathematics

1 answer:

notka56 [123]3 years ago

6 0

Answer:

21/35

Step-by-step explanation:

Given :

A right angled triangle with sides 28 , 35 ,21 .

And we need to find the value of cos A. We know that cosine is the ratio of base and Hypotenuse. So that ,

$:\implies$ cos A = b/h

$:\implies$ cosA = 21/35

$:\implies$ Hence the required Answer is 21/35.

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A number that multiplies to 30 and adds up to 13

-Dominant- [34]

Answer:

3 and 10

Step-by-step explanation:

5 0

3 years ago

9/16+7/8= A.)1-3/16inches B.)1-7/16inches C.)1-11/16inches D.)1/-13/16inches

anzhelika [568]

Answer:

hey can you show me the pic because the question doesn't make any sense

8 0

2 years ago

Fractions and Mixed numbers:

LiRa [457]

28/8 = 3 remainder 4 so 3 4/8(fraction) or 3 1/2
You would want to divide the minutes to the songs so you can find out how long one song is, but sense there was a remainder you could turn it into a fraction or you could keep diving. In this case you would want to stop. To find the fraction here is a formula the divisor is the denominator, the numerator is the remainder and the whole number is the number you get that is behind the remainder

3 0

3 years ago

(1 point) The effectiveness of a new bug repellent is tested on 18 subjects for a 10 hour period. Based on the number and locati

jolli1 [7]

Answer:

z=1.59

If we compare the p value and the significance level given $\alpha=0.025$ we see that $p_v>\alpha$ so we can conclude that we fail to reject the null hypothesis, so we can conclude that the mean repellency of the new bug repellent is greater than 89% at 0.025 of signficance.

Step-by-step explanation:

1) Data given and notation

$\bar X=0.92$ represent the mean effectiveness of a new bug repellent for the sample

$\sigma=0.08$ represent the population standard deviation for the sample

$n=18$ sample size

$\mu_o =0.89$ represent the value that we want to test

$\alpha=0.025$ represent the significance level for the hypothesis test.

t would represent the statistic (variable of interest)

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

State the null and alternative hypotheses.

We need to conduct a hypothesis in order to determine if the mean repellency of the new bug repellent is greater than 89% or 0.89, the system of hypothesis would be:

Null hypothesis: $\mu \leq 0.89$

Alternative hypothesis: $\mu > 0.89$

We don't know the population deviation, and the sample size <30, so for this case is better apply a t test to compare the actual mean to the reference value, and the statistic is given by:

$t=\frac{\bar X-\mu_o}{\frac{s}{\sqrt{n}}}$ (1)

t-test: "Is used to compare group means. Is one of the most common tests and is used to determine if the mean is (higher, less or not equal) to an specified value".

Calculate the statistic

We can replace in formula (1) the info given like this:

$t=\frac{0.92-0.89}{\frac{0.08}{\sqrt{18}}}=1.59$