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## High school geometry

### Course: High school geometry>Unit 9

Lesson 3: Volume and surface area

# Applying volume of solids

Calculate the volume of a grain hopper and then use the given rate to solve an applied problem. Created by Sal Khan.

## Want to join the conversation?

• Can't we also find the radius of the smaller cone by using the fact that the cones are similar? That is, if they are similar? Instead of taking a cross section and proving that the triangles in the cross section are similar... Is there any situation where this won't work? • Sal does that at when he sets up the equation r/10=6/8 to find r= 7.5. Since it is a single cone, each measure will be proportional
• what software does sal use? • when u have a can of beans and the height is 11 and the rades is 12 what will be an answer. my mom really needs to know because we r going to be using some beans tonight with dinner. yummmmmmmmmmmmmmy. also we r having hot dog wennies but I will save that problem for later. • have you played Elden Ring because there is a secret quest that asks a similair question to this actually! pretty cool
(1 vote) • At about in the video, Sal multiplies 6 by 1/3. Wouldn't he have to do the same for the 7.5? Why doesn't he?

At , he says that dividing by 1/10 is the same as multiplying by 10. How is this possible? Also, why does he multiply by 10?  