BMAT question help

2009 section 1 question 35. I am stuck with this question. I would be grateful if someone kind could explain it for me
Scottish agricultural output
1997: Sheep => 245.1 million euro
1998: Sheep => 237.4 million euro

35. If the pound fell by 5% in 1998 and the drop in value of sheep was entirely due to this, approximately what percentage of sheep is exported. A. 3% B. 5% C. 8% D. 37% E. 63%

Note: My solution is this. 245.1 is 100%. 2.451 is 1%. x% of sheep is exported at normal 2.451. (100-x)% of sheep is sold at 5% lower price since pound dropped by 5%. This means (2.451*x)+(2.451*0.95*(100-x))=237.4 Thus 2.451*(x+0.95*(100-x))=237.4 2.451*(x+95-0.95x)=237.4 x=37%

The answer is E. 63%. but why?

Reply 1

mqb2766

Pls stop spamming this question and if necessary post in the bmat thread as youve been advised to.

It would have been better to reply to the original post in maths (f38), but a couple of things
* calculators are not allowed in bmat and it looks like youre using one
* work out the (approximate) percentage reduction for 1997-1998. Comparing that with 5% gives you the percentage of sheep exported

(edited 1 year ago)

Reply 2

username5998581

Original post by mqb2766

You can just ignore it if you want. No need to be so touchy. The bmat thread was more about things like date, exam etc. It wasn't about exam questions, so I hesitated to post it there. Plus even though it is bmat question, the question i asked is about math so logically i don't think it is wrong to post it here. And to be honest, I didn't find the posting icon in the bmat thread. So I took a second advice of showing my thought process and posted it again.

I also wanted to know why comparing it to 5% gave out the number of sheep exported. Not the process. The key word is "whyyy"? I am sorry if my question sounds dumb but I am posting it because I can't understand it. From my understanding, the student room exists for asking questions

(edited 1 year ago)

Reply 3

mqb2766

Original post by iyoyiyoy

You can just ignore it if you want. No need to be so touchy. The bmat thread was more about things like date, exam etc. It wasn't about exam questions, so I hesitated to post it there. Plus even though it is bmat question, the question i asked is about math so logically i don't think it is wrong to post it here. And to be honest, I didn't find the posting icon in the bmat thread. So I took a second advice of showing my thought process and posted it again.

I also wanted to know why comparing it to 5% gave out the number of sheep exported. Not the process. The key word is whyyy? I am sorry if my question sounds dumb but I am posting it because I can't understand it.

The spamming is not being touchy, its so people dont waste time replying to identical threads which have already been answered. You could have just replied with your working to the original/bmat thread as asked.

You could do a simple thought process to understand why. If 0% of the sheep were exported, there would be no reduction in 1998. If 100% of the sheep were exported, the percentage reduction in 1998 would be 5%. So comparing the actual percentage reduction with 5% gives the percentage exported.

(edited 1 year ago)

Reply 4

mqb2766

Original post by iyoyiyoy

2009 section 1 question 35.

I am stuck with this question. I would be grateful if someone kind could explain it for me :smile:

35. If the pound fell by 5% in 1998 and the drop in value of sheep was entirely due to this, approximately what percentage of sheep is exported.
A. 3%
B. 5%
C. 8%
D. 37%
E. 63%

Note:
Scottish agricultural output
1997: Sheep => 245.1 million euro
1998: Sheep => 237.4 million euro

The answer is E. but why?

Its generally good to post some form of attempt. Did you work out the percentage change in output? Is it 5%, if not why?

Note there is a bmat thread at https://www.thestudentroom.co.uk/showthread.php?t=7211426

(edited 1 year ago)

Reply 5

alifelonglearner

Speed is of the essence with these questions. Note that the potential answers are very different in scale, and so we can work very roughly - no calculator is needed to determine that the correct answer is around 60%. If you insist on careful working/calculation/algebra then you’ll lose too much time.

Follow the starting advice given above and challenge yourself to see what you can work out without a calculator.