Please help me !!!!!!!!

juin [17]

Answer:

9

Step-by-step explanation:

I think what they are asking is to subtract the 3 tokens from 21 tokens he already has giving us 18. and since it says "Twice the number of tokens" I'm assuming you divide 2 from 18 giving you 9 tokens.

5 0

3 years ago

A solid is formed by adjoining two hemispheres to the ends of a right circular cylinder. An industrial tank of this shape must h

mestny [16]

Answer:

Radius =6.518 feet

Height = 26.074 feet

Step-by-step explanation:

The Volume of the Solid formed = Volume of the two Hemisphere + Volume of the Cylinder

Volume of a Hemisphere $=\frac{2}{3}\pi r^3$

Volume of a Cylinder $=\pi r^2 h$

Therefore:

The Volume of the Solid formed

$=2(\frac{2}{3}\pi r^3)+\pi r^2 h\\\frac{4}{3}\pi r^3+\pi r^2 h=4640\\\pi r^2(\frac{4r}{3}+ h)=4640\\\frac{4r}{3}+ h =\frac{4640}{\pi r^2} \\h=\frac{4640}{\pi r^2}-\frac{4r}{3}$

Area of the Hemisphere = $2\pi r^2$

Curved Surface Area of the Cylinder = $2\pi rh$

Total Surface Area=

$2\pi r^2+2\pi r^2+2\pi rh\\=4\pi r^2+2\pi rh$

Cost of the Hemispherical Ends = 2 X Cost of the surface area of the sides.

Therefore total Cost, C

$=2(4\pi r^2)+2\pi rh\\C=8\pi r^2+2\pi rh$

Recall: $h=\frac{4640}{\pi r^2}-\frac{4r}{3}$

Therefore:

$C=8\pi r^2+2\pi r(\frac{4640}{\pi r^2}-\frac{4r}{3})\\C=8\pi r^2+\frac{9280}{r}-\frac{8\pi r^2}{3}\\C=\frac{9280}{r}+\frac{24\pi r^2-8\pi r^2}{3}\\C=\frac{9280}{r}+\frac{16\pi r^2}{3}\\C=\frac{27840+16\pi r^3}{3r}$

The minimum cost occurs at the point where the derivative equals zero.

$C^{'}=\frac{-27840+32\pi r^3}{3r^2}$

$When \:C^{'}=0$

$-27840+32\pi r^3=0\\27840=32\pi r^3\\r^3=27840 \div 32\pi=276.9296\\r=\sqrt[3]{276.9296} =6.518$

Recall:

$h=\frac{4640}{\pi r^2}-\frac{4r}{3}\\h=\frac{4640}{\pi*6.518^2}-\frac{4*6.518}{3}\\h=26.074 feet$

Therefore, the dimensions that will minimize the cost are:

Radius =6.518 feet

Height = 26.074 feet

5 0

3 years ago

There verticles of a rectangle are shown on the grid what are the coordinates of the missing vertex 3,5,6

Nadusha1986 [10]

Answer:

Step-by-step explanation:

Since,

It's a rectangle so it will be formed on the coordinate which is 3units above dot(3,5) in picture where above the dot there is no point .

7 0

3 years ago

A mule deer can run one over four of a mile in 25 seconds. At this rate, which expression can be used to determine how fast a mu

geniusboy [140]

Speed (v) = distance (d) / time (t)
so either the second or third. if this is realistic deer can't run 100 miles per hour so is say the second initially but to check what is .25miles/25s convert to hours. (3600 seconds in an hour) so .25*3600=900 then 900miles/25hour= 36miles/ hour.

7 0

3 years ago

Se compró un artículo en S/. 219. ¿Qué precio debe fijarse para su venta al público?, para que haciendo un descuento del 25% tod

MrMuchimi

Answer:

342,1875

Step-by-step explanation:

Dado

Precio de compra del artículo = 219

Precio de venta cuando el descuento dado es 25% = 219 + 0,25 * 219 = 273,75

Para otorgar un descuento del 25%, este producto debe estar marcado a un precio un 25% más alto que los precios de venta = 273,75 + 0,25 * 273,75 = 342,1875

8 0

3 years ago