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        riddles >> general problem-solving / chatting / whatever >> electrical consumption
        
(Message started by: kennetha on Mar 6^th, 2007, 3:45am)

Title: electrical consumption
Post by kennetha on Mar 6^th, 2007, 3:45am

Hi all

What if ...A container was plugged on the 15 Jan and unplugged on 22nd Feb and another container was plugged on the 9th Feb and unplugged on the 28 th Feb. Electricy consumption from the 15 th Jan to the 28 th Feb was 345 units. Assuming that both containers consume the same amount of electricity what is the average daily. 14 days overlap. Is it possible to solve it?

Title: Re: electrical consumption
Post by towr on Mar 6^th, 2007, 5:41am

on 03/06/07 at 03:45:19, kennetha wrote:

Is it possible to solve it?

Yes, it is.
Assuming you want the average daily consumption per container (because the average total would be rather trivial), just count the days from 9th feb to 22nd feb double and the rest once.

Title: Re: electrical consumption
Post by Sir Col on Mar 6^th, 2007, 11:19am

Let x be the average daily units consumed.
First device runs for 39 days (15 Jan-22 Feb), using 39x units.
Second device runs for 20 days (9 Feb-28 Feb), using 20x units.
Total units, 39x+20x = 59x = 345 => average daily units, x ~= 5.85.

Alternatively, as towr suggested, consider one device running for 45 days (15 Jan-28 Feb), using 45x units of electricity. The overlap, where two devices are running simultaneously, can be considered to be equivalent to one device running for an additional 14 days, using 14x units. Hence 45x+14x = 59x units used in total, which leads to the same result.

Title: Re: electrical consumption
Post by THUDandBLUNDER on Mar 6^th, 2007, 12:07pm

Sir Col, he asked only if it is possible to solve it; not to do his homework for him. ;)

Title: Re: electrical consumption
Post by kennetha on Mar 6^th, 2007, 9:38pm

Thanks guys

much appriciated