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Comment on Precious Metals
On the question about 8
Your counter-example assumes
Your counter-example assumes that the data values are rounded to the nearest integer. However, there is nothing in the question that confirms this assumption.
So, we must assume that the given percentages are exact values. So, for example, Country B produced 30% of the Rhenium (and not 30.4% as you suggest)
Hello,
for the second statement how we concluded that total production of Country B&C will be 150 since when they doubled production we can consider only doubled amount not the sum of doubled+normal production.
Sorry for the confusion. We
Sorry for the confusion. We aren't saying that the total production from countries B and C is 150; we're saying that the NEW total for ALL of the counties (after B and C doubled their production) is 150 units.
We started by seeing what would happen if the original total volume of Rhenium is 100 units.
So, we can calculate the production of each country:
Country A: 4 units
Country B: 30 units
Country C: 20 units
Country D: 15 units
Country E: 8 units
Country F: 2 units
All other countries: 21 units
TOTAL = 100 units
If countries B and C DOUBLED their production, we get:
Country A: 4 units
Country B: 60 units
Country C: 40 units
Country D: 15 units
Country E: 8 units
Country F: 2 units
All other countries: 21 units
As we can see, the NEW production total = 150 units
Of these 150 units, Country D produced 15 units (i.e., 10% of the NEW production total.
Thank you Brent,
What I do not understand is that sum of all volume altogether is 79 before doubling the production and after doubled it is 119, Now I am confusing how it happens to be 100 and 150 when D=15 units. I mean when we consider D=15 then how we can calculate other countries more units than they are.
Sorry, I forgot to add in the
Sorry, I forgot to add in the row representing all OTHER countries (who produce the remaining 21% of rhenium).
I've edited my response above.
Therefore by the current
The answer to the middle
The answer to the middle question is YES.
If countries B and C had DOUBLED their production, the NEW production total = 150 units (see my calculations above)
Country D produced 15 of those 150 (hypothetical) units, which means country D produced 10% of the total.
Thanks a lot for the very
for a) can you just check
so that 17% + 6% + 8% is less than 50%+ required to answer the question?
That is perfectly sound
That is perfectly sound reasoning - nice work!
Cheers,
Brent
Hi Brent!
Can you kindly re-explain the first statement (a)?
I fully understand statements (b)and (c), but I couldn't understand statement (a).
Thank you very much!
Hi Lina,
Hi Lina,
Here's a different way to explain why statement (a) isn't true:
The main issue here is that the chart only refers to 6 of the world's countries.
We know that countries F and B are the 1st and 3rd leading countries when it comes to osmium production, but we don't know anything about the country that's 2nd in osmium production. I'll refer to this 2nd country as the MISSING country.
When it comes to bismuth production, countries F and B combined account for 23% of production. So, the only way for the top 3 osmium producers to produce over half of the world's bismuth would be for the MISSING country to produce at least 27% of the world's bismuth. This, however, is impossible because the chart already accounts for 92% of the world's bismuth production. So, even if the MISSING country produced the remaining 8% of bismuth, the top 3 osmium producers still wouldn't produce more than half of the world's bismuth.
Does that help?
Perfect, all clear. Thank you
Hi Brent, to clarify for
That's correct.
That's correct.
Thanks Brent for confirmation
As confused with a post above stating that the NEW total for ALL of the counties (after B and C doubled their production) is 150 units.
Hi Brent, for C, how could we
Yes we have to assume that
Yes we have to assume that the ENTIRE world's production of rhenium accounts for 100% of the rhenium production.
The main idea here is that there must be more than six countries producing rhenium. We know this because the six countries listed here account for only 79% of the world's production.
So some additional countries must account for the remaining 21% of the world's production.
For example, if I have a bunch of apples, and I give you 79% of them, then I must have kept the remaining 21% of the apples for myself.
Does that help?
Get it thanks Brent.