Hi. Here are some steps:
If you don't know the formula for the volume of a cone, then please look it up. (Use your textbook's index, or google it.)
Let r = radius of cone B
Let h = height of cone B
Let 25∙Pi = volume of cone B
Use the expressions above in the volume formula, to write an equation for cone B.
Now, what expression can we write for the radius of cone A?
What expression can we write for the height of cone A?
Let V = volume of cone A
Again, use the volume formula, to write an equation for cone A.
Next, use algebra to rearrange both equations so that the right-hand sides looks like this:
Pi∙r^2∙h
Once you've done that, you can see that the two left-hand sides are equal. So, set them equal to one another (to form a new equation), and then solve it for V.
If you'd like more help, please follow the guidelines and show your work and/or ask specific questions. Cheers
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