Say the floor of my living room were 18 foot longer and 12 foot narrower, it would take 16 square yards less carpet; but if it were 12 foot shorter and 12 foot wider, it would not change its area. What are its dimensions, please?
Carpet Laying Calculation
Dec 12, 2015
37 Replies
When I looked at this, I though it's going to be one of those problems where the minimum dimension is negative; but it isn't even that subtle.
Please sir, can I use a calculator or look up your question on the Internet to crib the answer?
Well if not, then how about 48 foot long and 36 foot wide. Do I win a Milky Bar?
I quite liked the question. Easy to solve with one little thing to watch for.
Let length = L, width = W.
1) (L+18).(W-12) = LW - 144 2) (L-12).(W+12) = LW 1) LW - 12L +18W - 216 = LW -144 18W - 12L = 72 3W - 2L = 12 2) LW + 12L - 12W - 144 = LW L - W = 12 L = W +12Substituting L = W + 12 in 1)
3W - 2W - 24 = 12 W = 36 ft so L = 48 ft
I like your style :-)
Right answer, but you didn't show your working, so no cigar for you. ;->
Right answer and you showed your working; well done! Unfortunately, you were beaten to it by Pamela who was quicker, so no cigar for you. ;->
A Harrods hamper. Least you can do
I prayed for inspiration from the father of algebra Diophantus and, without understanding how, the answer jumped into my mind.
Diophantus and me want that Milky Bar to share between us. :-)
No one gets a prize? It's a swizz. We want our money back!
bah! yards and feet. I didn't notice and got it wrong.
Hmmm, big room. You a Dook, or summing?
48ft long, 36ft wide.Need something a bit harder next time.
Neither did I, but I really can't be arsed.
So
14.6304m by 10.9728m in proper money:-)
That's a nice maths problem of the sort I would like to get my young 16 year old relative to attempt. The necessary maths theory is not particularly advanced but it needs a little bit of peristence.
Are there more problems at about the same level (perhaps not just to do with algebra) where that one came from? By contrast, your water flow problem would be too advanced.
There are dozens of puzzle books but they are often trivial or far too hard.
Thanks for any info.
Pamela is a lady. She doesn't smoke cigars.
Bill
Why should you be expected to show your working? You used female intuition.
Bill
Certainly not at my expense, anyway. ;->
You'll struggle to find this kind of thing in print any more, thanks to dumbing down. The questions come from a 1950s Grammar School maths book. You can probably find plenty of similar books dirt cheap on Ebay and they are ***MILES*** better than anything published today. In fact for any subject where the science is settled, I now *always* go for something written in the 30s, 40s & 50s. The clarity and precision of language was
*way* better back then, too.Join the Discussion
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