1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
cluponka [151]
4 years ago
13

Biruk wants to buy a book for $15.25 and a book for $4.85. He wants to pay with one $20 bill. Use estimation to decide if this i

s reasonable. Explain to what place value to round for an estimate that is useful in this situation.
Mathematics
2 answers:
ycow [4]4 years ago
8 0
First round 15.25 to 15.30 and round 4.85 to 4.90 and then add you get 21.20  no it is not reasonable and you round to the decimal ones
Aloiza [94]4 years ago
6 0

Answer: It's not reasonable.

Step-by-step explanation:

Hi, to answer this question we have to add both book’s prices:

15.25 + 4.85 = $20.1

If he wants to pay with one $20 bill, it wouldn’t be reasonable, because:

20 <20.1

For an useful estimate, estimate to the nearest tenth:

15.30 +4.90 = 20.2

Still, he can’t afford the books because he is lacking 20 cents.

Feel free to ask for more if needed or if you did not understand something.

You might be interested in
Use the Divergence Theorem to evaluate S F · dS, where F(x, y, z) = z2xi + y3 3 + sin z j + (x2z + y2)k and S is the top half of
GenaCL600 [577]

Close off the hemisphere S by attaching to it the disk D of radius 3 centered at the origin in the plane z=0. By the divergence theorem, we have

\displaystyle\iint_{S\cup D}\vec F(x,y,z)\cdot\mathrm d\vec S=\iiint_R\mathrm{div}\vec F(x,y,z)\,\mathrm dV

where R is the interior of the joined surfaces S\cup D.

Compute the divergence of \vec F:

\mathrm{div}\vec F(x,y,z)=\dfrac{\partial(xz^2)}{\partial x}+\dfrac{\partial\left(\frac{y^3}3+\sin z\right)}{\partial y}+\dfrac{\partial(x^2z+y^2)}{\partial k}=z^2+y^2+x^2

Compute the integral of the divergence over R. Easily done by converting to cylindrical or spherical coordinates. I'll do the latter:

\begin{cases}x(\rho,\theta,\varphi)=\rho\cos\theta\sin\varphi\\y(\rho,\theta,\varphi)=\rho\sin\theta\sin\varphi\\z(\rho,\theta,\varphi)=\rho\cos\varphi\end{cases}\implies\begin{cases}x^2+y^2+z^2=\rho^2\\\mathrm dV=\rho^2\sin\varphi\,\mathrm d\rho\,\mathrm d\theta\,\mathrm d\varphi\end{cases}

So the volume integral is

\displaystyle\iiint_Rx^2+y^2+z^2\,\mathrm dV=\int_0^{\pi/2}\int_0^{2\pi}\int_0^3\rho^4\sin\varphi\,\mathrm d\rho\,\mathrm d\theta\,\mathrm d\varphi=\frac{486\pi}5

From this we need to subtract the contribution of

\displaystyle\iint_D\vec F(x,y,z)\cdot\mathrm d\vec S

that is, the integral of \vec F over the disk, oriented downward. Since z=0 in D, we have

\vec F(x,y,0)=\dfrac{y^3}3\,\vec\jmath+y^2\,\vec k

Parameterize D by

\vec r(u,v)=u\cos v\,\vec\imath+u\sin v\,\vec\jmath

where 0\le u\le 3 and 0\le v\le2\pi. Take the normal vector to be

\dfrac{\partial\vec r}{\partial v}\times\dfrac{\partial\vec r}{\partial u}=-u\,\vec k

Then taking the dot product of \vec F with the normal vector gives

\vec F(x(u,v),y(u,v),0)\cdot(-u\,\vec k)=-y(u,v)^2u=-u^3\sin^2v

So the contribution of integrating \vec F over D is

\displaystyle\int_0^{2\pi}\int_0^3-u^3\sin^2v\,\mathrm du\,\mathrm dv=-\frac{81\pi}4

and the value of the integral we want is

(integral of divergence of <em>F</em>) - (integral over <em>D</em>) = integral over <em>S</em>

==>  486π/5 - (-81π/4) = 2349π/20

5 0
3 years ago
PLEASE PLEASE I NEED HELP ASAP
Sidana [21]
AE = AC = 4

m<CAB = 60 (equilateral triangle)
m<CAE = 90 (square)

m<BAE = 150 (= 60 + 90)

Triangle BAE is isosceles since AB = AE;
therefore, m<AEB = m<ABE.

m<AEB + m<ABE + m<BAE = 180

m<AEB + m< ABE + 150 = 180

m<AEB + m<AEB = 30

m<AEB = 15

In triangle ABE, we know AE = AB = 4;
we also know m<BAE = 150, and m<AEB = 15.

We can use the law of sines to find BE.

BE/(sin 150) = 4/(sin 15)

BE = (4 sin 150)/(sin 15)

BE = 7.727

3 0
3 years ago
Which fraction is equivalent to <br> 2<br> 10
yawa3891 [41]

Answer:

Fraction Equivalent Fractions

1/5 2/10 4/20

2/5 4/10 8/20

3/5 6/10 12/20

4/5 8/10 16

Step-by-step explanation:

THIS IS ANSWER PLS MARK BRAINLIST

7 0
3 years ago
Mel has to put the greatest number of
Dmitry_Shevchenko [17]

Mel should use the least  common multiple to solve the problem

<u>Solution:</u>

Given, Mel has to put the greatest number of bolts and nuts in each box so each box has the same number of bolts and the same number of nuts.  

We have to find that should Mel use the greatest common factor or the least common multiple to solve the problem?

He should use least common multiple.

Let us see an example, suppose 12 bolts and nuts are to be fit in 6 boxes.

Then, if we took H.C.F of 12 and 6, it is 6, which means 6 bolts and nuts in each box, but, after filling 2 boxes with 6 bolts and nuts, there will be nothing left, which is wrong as remaining boxes are empty.

So the remaining method to choose is L.C.M.

Hence, he should use L.C.M method.

6 0
3 years ago
Noah owns a DJ business. He charges $100 booking fee plus $40 per hour. Write an equation and graph
nikklg [1K]
The equation would be 100+40x
7 0
3 years ago
Read 2 more answers
Other questions:
  • I’ve been at this for 3 hours. Please help.
    14·1 answer
  • Donna's Deli delivers lunches for $7 per person plus a $35 delivery fee. Larry's Lunches delivers lunches for $11 per person.
    7·1 answer
  • How do you find the ratio of a number?
    8·1 answer
  • Examine the inequality and its graph. Which values are part of the solution set? Check all that apply.
    6·2 answers
  • What is the answer to this problem- 2(t+1)=10?
    11·1 answer
  • What is Two thirds of four forths-fifths of a dozen
    11·1 answer
  • Help me with this question pleaseee
    7·1 answer
  • Lila decided to make more baked goods for the bake sale. She used 1/8 less flour to make bread to make cookies. She used 1/4 mor
    8·2 answers
  • Which of the following sets of ordered pairs represents a function?
    11·2 answers
  • Please help.. (y-value = ??)
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!