Article View: alt.school.homework-help
Article #64Re: Help on a Maths problem
From: Rehn
Date: Mon, 01 Jul 2002 19:03
Date: Mon, 01 Jul 2002 19:03
140 lines
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7818 bytes
This is a multi-part message in MIME format. ------=_NextPart_000_001D_01C2213A.4679C380 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable "Jonathan" <jp_wells@optusnet.com.au> wrote in message = news:3d1eedb4$0$25797$afc38c87@news.optusnet.com.au... > As part of a school assignment I have to complete these two problems, = but I > have no idea as to how to do them, I was wondering anyone knows how to = do > them? >=20 > 1) The product of two positive number is 12. Find the least value of = their > sum. Is there a largest value? (10 marks) x*y x+y 2*6 =3D 12 2+6=3D8 try this with all - try using a spreadsheet. = 1*12 2*6 3*4 etc make a column for x and for y then make a column for = the sum of the two.=20 > 2) The sum of the base radius and perpendicular height of a cylinder = is > 12cm. Find the maximum volume of the cyclinder. (10 marks) Make a list of all possible combinations of numbers - lets call them r = (for radius) and h (for height)=20 we know r+h=3D12 we also know that the area of a circle is =CE=A0r2 so times the number = you have as r by pie then square it. U can do this on a spreadsheet. We also know that the area of the base of a cylinder times the height of = the cylinder makes the area of a cylinder. Imagine loads of slices of = saliami squished together ! The maxuim volume is the numbers which multiply together to make the = highest number.=20 I imagine for both of these you would need to show your workings, = produce graphs if you can, formulaes and if it is a courseworky type = thing - like we have here in britain then extending it to numbers other = than twelve for the two questions and seeing if you can (probably) = algerbricaly explain for all numbers. Good luck - I notice allot of people have posted answers here - or more = likely help so maybe you could tell us how you got along. =20 >=20 > Thankyou >=20 >=20 ------=_NextPart_000_001D_01C2213A.4679C380 Content-Type: text/html; charset="utf-8" Content-Transfer-Encoding: quoted-printable =EF=BB=BF<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <HTML><HEAD> <META http-equiv=3DContent-Type content=3D"text/html; charset=3Dutf-8"> <META content=3D"MSHTML 6.00.2716.2200" name=3DGENERATOR> <STYLE></STYLE> </HEAD> <BODY bgColor=3D#ffffff> <DIV><FONT face=3DArial size=3D2></FONT> </DIV> <DIV><FONT face=3DArial size=3D2>"Jonathan" <</FONT><A=20 href=3D"mailto:jp_wells@optusnet.com.au"><FONT face=3DArial=20 size=3D2>jp_wells@optusnet.com.au</FONT></A><FONT face=3DArial = size=3D2>> wrote in=20 message </FONT><A=20 href=3D"news:3d1eedb4$0$25797$afc38c87@news.optusnet.com.au"><FONT = face=3DArial=20 size=3D2>news:3d1eedb4$0$25797$afc38c87@news.optusnet.com.au</FONT></A><F= ONT=20 face=3DArial size=3D2>...</FONT></DIV> <DIV><FONT face=3DArial size=3D2>> As part of a school assignment I = have to=20 complete these two problems, but I<BR>> have no idea as to how to do = them, I=20 was wondering anyone knows how to do<BR>> them?<BR>> <BR>> = 1) The=20 product of two positive number is 12. Find the least value of = their<BR>> sum.=20 Is there a largest value? (10 marks)<BR>x*y x+y 2*6 =3D 12 2+6=3D8 = try this=20 with all - try using a spreadsheet. 1*12 2*6 3*4 etc make a column for x = and for=20 y then make a column for the sum of the two. </FONT></DIV> <DIV><BR><FONT face=3DArial size=3D2>> 2) The sum of the base = radius and=20 perpendicular height of a cylinder is<BR>> 12cm. Find the maximum = volume of=20 the cyclinder. (10 marks)<BR>Make a list of all possible = combinations of=20 numbers - lets call them r (for radius) and h (for=20 height) </FONT></DIV> <DIV><FONT face=3DArial size=3D2>we know r+h=3D12</FONT></DIV> <DIV><FONT face=3DArial size=3D2>we also know that the area = of a circle=20 is <FONT face=3DAndy><SPAN lang=3DDE=20 style=3D"FONT-SIZE: 18pt; FONT-FAMILY: 'Comic Sans MS'; = mso-bidi-font-size: 12.0pt; mso-fareast-font-family: 'Times New Roman'; = mso-bidi-font-family: 'Times New Roman'; mso-ansi-language: DE; = mso-fareast-language: EN-US; mso-bidi-language: AR-SA"><FONT=20 size=3D3>=CE=A0</FONT></SPAN><SPAN lang=3DDE=20 style=3D"FONT-SIZE: 18pt; FONT-FAMILY: 'Comic Sans MS'; = mso-bidi-font-size: 12.0pt; mso-fareast-font-family: 'Times New Roman'; = mso-bidi-font-family: 'Times New Roman'; mso-ansi-language: DE; = mso-fareast-language: EN-US; mso-bidi-language: AR-SA"><SUP><FONT=20 size=3D3>r2</FONT> </SUP></SPAN></FONT></FONT><FONT face=3DArial=20 size=3D2>so times the number you have as r by pie then square = it. U can=20 do this on a spreadsheet.</FONT></DIV> <DIV><FONT face=3DArial size=3D2>We also know that the area of the base = of a=20 cylinder times the height of the cylinder makes the area of a cylinder. = Imagine=20 loads of slices of saliami squished together !</FONT></DIV> <DIV><FONT face=3DArial size=3D2>The maxuim volume is the numbers which = multiply=20 together to make the highest number. </FONT></DIV> <DIV><FONT face=3DArial size=3D2></FONT> </DIV> <DIV><FONT face=3DArial size=3D2>I imagine for both of these = you would=20 need to show your workings, produce graphs if you can, formulaes and if = it is a=20 courseworky type thing - like we have here in britain = then extending=20 it to numbers other than twelve for the two questions and seeing if = you=20 can (probably) algerbricaly explain for all = numbers.</FONT></DIV> <DIV><FONT face=3DArial size=3D2></FONT> </DIV> <DIV><FONT face=3DArial size=3D2>Good luck - I notice allot of people = have posted=20 answers here - or more likely help so maybe you could tell us how you = got=20 along. <BR>> <BR>> Thankyou<BR>> = <BR>>=20 </FONT></DIV></BODY></HTML> ------=_NextPart_000_001D_01C2213A.4679C380--
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