All categories

3 years ago

Which expression is the correct translation of the following word phrase?

1 answer:

3 0

Hey, there!

The parentheses would make it multiplication
The word sum means add
A number was unknown, so we will label it as "x"

So, let's see what we're working with here!

If you chose "Option A" the question would be "five multiplied by a number and the sum of 3" (that doesn't give you the right answer"
For B. same thing with option A
For "Option C" its not asking you "a number with sum of three times five"

So, this leaves "Option D." as your answer because 3 is getting multiplied by the sum of some number and five

Good luck on your assignment and enjoy your day!

~MeIsKaitlyn:)

You might be interested in

Tyra wants to arrange 32 tiles in equal rows and columns. How many ways could she organize the tiles? List the factors.

Black_prince [1.1K]

1,32 2,16, 4,8
That's all I got so it's 3
Sorry if I got it wrong or missed some

4 0

3 years ago

The height of a triangle is 15cm, the base is 40cm and the other two side are 25cm.

morpeh [17]

The formula for the area of a triangle is base*height/2. So lets input the number.

15*40=600/2=300 cm2

6 0

3 years ago

5-7 <-3 : what is the simplified form of the inequality below ?

Makovka662 [10]

Answer:

5<4

Step-by-step explanation:

This inequality is not correct though.

5-7+7<-3+7

5<4

7 0

3 years ago

Suppose that W1, W2, and W3 are independent uniform random variables with the following distributions: Wi ~ Uni(0,10*i). What is

nadya68 [22]

I'll leave the computation via R to you. The $W_i$ are distributed uniformly on the intervals $[0,10i]$ , so that

$f_{W_i}(w)=\begin{cases}\dfrac1{10i}&\text{for }0\le w\le10i\\\\0&\text{otherwise}\end{cases}$

each with mean/expectation

$E[W_i]=\displaystyle\int_{-\infty}^\infty wf_{W_i}(w)\,\mathrm dw=\int_0^{10i}\frac w{10i}\,\mathrm dw=5i$

and variance

$\mathrm{Var}[W_i]=E[(W_i-E[W_i])^2]=E[{W_i}^2]-E[W_i]^2$

We have

$E[{W_i}^2]=\displaystyle\int_{-\infty}^\infty w^2f_{W_i}(w)\,\mathrm dw=\int_0^{10i}\frac{w^2}{10i}\,\mathrm dw=\frac{100i^2}3$

so that

$\mathrm{Var}[W_i]=\dfrac{25i^2}3$

Now,

$E[W_1+W_2+W_3]=E[W_1]+E[W_2]+E[W_3]=5+10+15=30$

and

$\mathrm{Var}[W_1+W_2+W_3]=E\left[\big((W_1+W_2+W_3)-E[W_1+W_2+W_3]\big)^2\right]$

$\mathrm{Var}[W_1+W_2+W_3]=E[(W_1+W_2+W_3)^2]-E[W_1+W_2+W_3]^2$

We have

$(W_1+W_2+W_3)^2={W_1}^2+{W_2}^2+{W_3}^2+2(W_1W_2+W_1W_3+W_2W_3)$

$E[(W_1+W_2+W_3)^2]$

$=E[{W_1}^2]+E[{W_2}^2]+E[{W_3}^2]+2(E[W_1]E[W_2]+E[W_1]E[W_3]+E[W_2]E[W_3])$

because $W_i$ and $W_j$ are independent when $i\neq j$ , and so

$E[(W_1+W_2+W_3)^2]=\dfrac{100}3+\dfrac{400}3+300+2(50+75+150)=\dfrac{3050}3$

giving a variance of

$\mathrm{Var}[W_1+W_2+W_3]=\dfrac{3050}3-30^2=\dfrac{350}3$

and so the standard deviation is $\sqrt{\dfrac{350}3}\approx\boxed{116.67}$

# # #

A faster way, assuming you know the variance of a linear combination of independent random variables, is to compute

$\mathrm{Var}[W_1+W_2+W_3]$

$=\mathrm{Var}[W_1]+\mathrm{Var}[W_2]+\mathrm{Var}[W_3]+2(\mathrm{Cov}[W_1,W_2]+\mathrm{Cov}[W_1,W_3]+\mathrm{Cov}[W_2,W_3])$

and since the $W_i$ are independent, each covariance is 0. Then

$\mathrm{Var}[W_1+W_2+W_3]=\mathrm{Var}[W_1]+\mathrm{Var}[W_2]+\mathrm{Var}[W_3]$

$\mathrm{Var}[W_1+W_2+W_3]=\dfrac{25}3+\dfrac{100}3+75=\dfrac{350}3$

and take the square root to get the standard deviation.

8 0

3 years ago

What is Qualitative Data and what is the discreate and Continuous in qualitative data?

boyakko [2]

Answer:

Qualitative data is the data that is not represented by numbers, for example, favorite food or country.

On the other hand, the quantitative data is represented by numbers and it is classified as discrete and continuous. The discrete data is the data that only can take specific values, for example, the number of people is always a whole number, there can't be 5.5 people. The continuous data is the data that can take decimal values, for example, the mass of an object can be 4.06 kg.

6 0

1 year ago