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 MathematicallyObtuse January 9th, 2011 06:54 AM

Ratios

How do I solve this?

I have two unknowns: # of votes David receives = 7/15 times some number to give 30 + some number.

 Chimoo January 9th, 2011 07:27 AM

Re: Ratios

If the ratio is 8:7 doesn't it just mean that David received 7*30 votes, which is 210? Or am I missing something silly

Or using simultaneous equations:

a - 30 = d
7/8a = d

8a - 240 = 8d
7a = 8d

a - 240 = 0
a = 240
d = 210

 soroban January 9th, 2011 07:45 AM

Re: Ratios

Hello, Chimoo!

Quote:
 If the ratio is 8:7, doesn't it just mean that David received 7x30 votes, which is 210 ? Or am I missing something silly? [color=beige] . [/color] [color=blue] no![/color]

Absolutely correct!

A terrific "eyeball" solution!

 MathematicallyObtuse January 9th, 2011 08:07 AM

Re: Ratios

Quote:
 Originally Posted by Chimoo If the ratio is 8:7 doesn't it just mean that David received 7*30 votes, which is 210? Or am I missing something silly Or using simultaneous equations: a - 30 = d 7/8a = d 8a - 240 = 8d 7a = 8d a - 240 = 0 a = 240 d = 210
Delightful! I wouldn't have seen that in a million years! Thank you :-)

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