CPhill

I assume here that "cost"  is the original cost to the seller....and we're trying to find the buyer's cost??

If so......the seller marks the $349.99 up by 41% = $493.49

Then......he discounts this by 23%  [ i.e., the sales price is now 77%  of $493.49]

So.....the buyer's cost is  .77 * $493.49 = $379.98

cuberoot (5)  - ?   = sqrt (5)         add ?  to both sides, subtract sqrt(5) from both sides

cubroot(5)  - sqrt(5)  =  ?

Yep, Rarinstraw.....a photo finish.....!!!!!

241 / 36 = 6 + 25/36   .....but....since we can't take a"partial" bus.....we'll need 7

That's what we're here for.......!!!!

Welome aboard, TC......!!!!!!

Go ahead and ask your question, Kellogg......we'll see if we can help you.....

Thanks, heureka........what method did you use for your solution?????

We are using the ring ["washer"]  method........see the explanation, here....

http://tutorial.math.lamar.edu/Classes/CalcI/VolumeWithRings.aspx

[Example 1 is very similar to this one]

Area = pi * (radius)^2  =    pi * (21 in)^2 = [ pi *441] in^2  ≈ 1385.44 in ^2