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anju
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50 books issued as per data (12*1 + 10*2 + 6*3)
average is 2 per student and total students are 30 so total books issued 30*2 = 60
60 - 50 = 10 books extra
max a student has issued is 3 books so in all 3+10 = 13 books is the mac that a student could have issued
average is 2 per student and total students are 30 so total books issued 30*2 = 60
60 - 50 = 10 books extra
max a student has issued is 3 books so in all 3+10 = 13 books is the mac that a student could have issued
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vishubn
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Number of students =30
2 - No books borrowed
12 people borrowed one book each---12 books
10-people borrowed 2 each - 20 books
6 peopel atleast 3 ---C
average =2
sum/30=2
number of books =60
so 60 books to be distributed amongst 28 people
Now 12 people take 12 books
10 people take 20 books
So remaining ius 60-10-20
which is 28 books remaining
no 6 people take min 3 so 6th person can take the max
so 5 taking minimum 3books -5*3=15 books
so 6th person can take the max - 13 books
2 - No books borrowed
12 people borrowed one book each---12 books
10-people borrowed 2 each - 20 books
6 peopel atleast 3 ---C
average =2
sum/30=2
number of books =60
so 60 books to be distributed amongst 28 people
Now 12 people take 12 books
10 people take 20 books
So remaining ius 60-10-20
which is 28 books remaining
no 6 people take min 3 so 6th person can take the max
so 5 taking minimum 3books -5*3=15 books
so 6th person can take the max - 13 books
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pepeprepa
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Write the average which will be 2 with the information they give you:
(2*0+12*1+10*2+6*x)/30=2
It gives:
32+6x=60
6x=28
You want the maximum number of book one of 6 guys can borrow, so let's write the equation like this to be clearer:
5x+y=28
y=28-5x
You want to Maximize y, so you need to Minimize x. However, you cannot give x 0 because the question told you they borrowed 3 books or more. So let's chose 3 for the 5 guys.
y=28-5*3
y=13
(2*0+12*1+10*2+6*x)/30=2
It gives:
32+6x=60
6x=28
You want the maximum number of book one of 6 guys can borrow, so let's write the equation like this to be clearer:
5x+y=28
y=28-5x
You want to Maximize y, so you need to Minimize x. However, you cannot give x 0 because the question told you they borrowed 3 books or more. So let's chose 3 for the 5 guys.
y=28-5*3
y=13
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lunarpower
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here's the deal:
if you want to maximize the number of books taken by one person, then you need to minimize the number of books taken by the other people.
incidentally, this is a really common theme in 'optimization' problems:
to maximize one quantity, minimize the others; to minimize one quantity, maximize the others.
this is supremely obvious in some circumstances - for instance, if a baseball team with a salary cap wants to pay superstar X as much as possible, it can only do so by paying all the other players as little as possible.
--
another common theme:
if you're given a statement about an average, then you should transform it into a statement about a sum.
--
if we follow both of the above points of advice, we arrive at the following solution:
first, realize that the 'average of 2 books' statement is really just a roundabout way of telling you that the 30 students took out a total of 60 books.
the mentioned quantities add up to 32 books, so you have to account for the other 28 books, among 6 students.
if you minimize the book count for five of the six students, that's 3 books per student = 15 books.
28 - 15 = 13 books for the lucky sixth student.
if you want to maximize the number of books taken by one person, then you need to minimize the number of books taken by the other people.
incidentally, this is a really common theme in 'optimization' problems:
to maximize one quantity, minimize the others; to minimize one quantity, maximize the others.
this is supremely obvious in some circumstances - for instance, if a baseball team with a salary cap wants to pay superstar X as much as possible, it can only do so by paying all the other players as little as possible.
--
another common theme:
if you're given a statement about an average, then you should transform it into a statement about a sum.
--
if we follow both of the above points of advice, we arrive at the following solution:
first, realize that the 'average of 2 books' statement is really just a roundabout way of telling you that the 30 students took out a total of 60 books.
the mentioned quantities add up to 32 books, so you have to account for the other 28 books, among 6 students.
if you minimize the book count for five of the six students, that's 3 books per student = 15 books.
28 - 15 = 13 books for the lucky sixth student.
Ron has been teaching various standardized tests for 20 years.
--
Pueden hacerle preguntas a Ron en castellano
Potete chiedere domande a Ron in italiano
On peut poser des questions à Ron en français
Voit esittää kysymyksiä Ron:lle myös suomeksi
--
Quand on se sent bien dans un vêtement, tout peut arriver. Un bon vêtement, c'est un passeport pour le bonheur.
Yves Saint-Laurent
--
Learn more about ron
--
Pueden hacerle preguntas a Ron en castellano
Potete chiedere domande a Ron in italiano
On peut poser des questions à Ron en français
Voit esittää kysymyksiä Ron:lle myös suomeksi
--
Quand on se sent bien dans un vêtement, tout peut arriver. Un bon vêtement, c'est un passeport pour le bonheur.
Yves Saint-Laurent
--
Learn more about ron
