Question

help!?? An hourglass consists of two sets of congruent composite figures on either end. Each composite figure is made up of a cone and a cylinder.
(medal will be given)

Answer 1

Each cone of the hourglass has a height of 12 millimeters. The total height of the sand within the top portion of the hourglass is 47 millimeters. The radius of both the cylinder and cone is 4 millimeters. Sand drips from the top of the hourglass to the bottom at a rate of 10π cubic millimeters per second. How many seconds will it take until all of the sand has dripped to the bottom of the hourglass?

6.4

62.4

8.5

56.0

Answer 2

@travisbrown372 @robtobey @hartnn help plz

Answer 3

Find the volume of the sand, and then divide the volume by the rate to come up with the time.

Disclaimer: When we're doing the calculation for the volume of the cone below, it's really only an estimate. We're assuming it's really a cone (i.e. that it comes to a point); but if that were the case, no sand would be able to fall. Nevertheless, that's how we're doing it.

The total volume of sand consists of the sand in the cone portion plus whatever sand is in the cylindrical portion of the hourglass. We'll call the total volume V, the conical volume Vcn, and the cylindrical volume Vcy.

V = Vcn + Vcy

The cone is 12mm high; and since the total amount of sand is 47mm high, that means the cone is entirely filled.

Vcn = (1/3)(pi)(r^2)(h)
Vcn = (1/3)(pi)(4^2)(12)
Vcn = 64pi

Now... if the sand is 47mm high but the cone is only 12mm high, that means the height of the sand in the cylinder is 47 - 12 = 35mm. So...

Vcy = (pi)(r^2)(h)
Vcy = (pi)(4^2)(35)
Vcy = 560pi

Now substitute back into your original equation.

V = Vcn + Vcy
V = 64pi + 560pi
V = 624pi

The sand drips at a rate of 10pi cu mm / sec.

624pi / 10pi = 62.4

The last answer is the correct one. It'll take 62.4 sec for all the sand to move from the top of the hourglass to the bottom.

Answer 4

if you take the volume of the sand in the cone (Volume of a cone =1/3*pi*r*r*h) and divide by the rate you will get units of mm/(mm/s)=seconds. If you ignore the 47, the volume of the top cone is 1/3*pi*16*12=200.96. when i divide that by the rate i get 200.96mm/(31.4mm/sec) =6.4seconds

Answer 5

http://openstudy.com/study#/updates/4f52d632e4b019d0ebb065c0

Answer 6

http://openstudy.com/study#/updates/4ffdf922e4b09082c06f477f

Answer 7

* A cylindrical water glass has a radius of 7 centimeters and a height of 14 centimeters. What is its volume rounded to the nearest hundredth?
718.38 cm3
1,436.76 cm3
2,155.13 cm3
4,310.27 cm3

* Ally is wearing a witch’s costume for Halloween. Her hat is in the shape of a cone with a diameter of 7 inches and a height of 12 inches. What is the volume of Ally’s hat? Use for 22/7 pi.
154 in3
180 in3
196 in3
462 in3

* A hamster ball has a radius of 18 centimeters. What is its volume written in terms of π?
432π cm3
4,374π cm3
5,832π cm3
7,776π cm3

* The small pipe has a radius of 10 feet and a height of 22 feet while the large pipe has a height of 33 feet. What is the volume of the large pipe in terms of π?
2,200π ft3
2,475π ft3
4,500π ft3
7,425π ft3

* A water ride at a local water park has a ride shaped like a cone that acts like a funnel whereby guests swirl around the cone until they drop through its center. There is one ride for adults and a similar, smaller version for children. If the adult ride has a radius of 25 feet and the child ride has a radius of 10 feet, what is the ratio between the volumes of each ride?
5:2
15:6
25:4
125:8

*
They provided trash cans to residents to dispose of their waste. All trash cans have a diameter of 1 meter and a height of 0.75 meters. What is the minimum number of trash cans required to dispose of 10 cubic meters of waste?
50
51

*Afunnel with a height of 3.42 inches.

The funnel has a diameter of 1.56 inches that includes a wall that is 0.125 inches thick. What is the maximum volume of the funnel rounded to the nearest hundredth?
1.18 in3
1.54 in3
2.18 in3
6.54 in3

*
The radius of the cone is 1.5 inches, and its height is 3 inches. If the diameter of the bubble gum ball is 0.5 inches, what is the closest approximation of the volume of the cone that can be filled with flavored ice?
0.07 in3
7.00 in3
7.07 in3
21.21 in3

*Each cone of the hourglass has a height of 12 millimeters. The total height of the sand within the top portion of the hourglass is 47 millimeters. The radius of both the cylinder and cone is 4 millimeters. Sand drips from the top of the hourglass to the bottom at a rate of 10π cubic millimeters per second. How many seconds will it take until all of the sand has dripped to the bottom of the hourglass?
6.4
8.5
56.0
62.4

Answer 8

http://inqu.us/updates/4f85a6f9e4b0505bf085b434

Answer 9

@travisbrown372 thx

Answer 10

ur welcome wow that was hard

Answer 11

sorry !