Rangpur Higher Secondary 2011/3
Forum rules
Please don't post problems (by starting a topic) in the "Higher Secondary: Solved" forum. This forum is only for showcasing the problems for the convenience of the users. You can post the problems in the main Divisional Math Olympiad forum. Later we shall move that topic with proper formatting, and post in the resource section.
Please don't post problems (by starting a topic) in the "Higher Secondary: Solved" forum. This forum is only for showcasing the problems for the convenience of the users. You can post the problems in the main Divisional Math Olympiad forum. Later we shall move that topic with proper formatting, and post in the resource section.
Rangpur Higher Secondary 2011/3
Problem 3:
If $3<f<4$ and $2<g<1$, then what is the range of possible values of $fg$?
If $3<f<4$ and $2<g<1$, then what is the range of possible values of $fg$?
 leonardo shawon
 Posts: 169
 Joined: Sat Jan 01, 2011 4:59 pm
 Location: Dhaka
Re: Rangpur Higher Secondary 2011/3
its $6<fg<4$
i did this way,, i multiple the upper limit and lower limit of f and g.
i did this way,, i multiple the upper limit and lower limit of f and g.
Ibtehaz Shawon
BRAC University.
long way to go .....
BRAC University.
long way to go .....

 Posts: 78
 Joined: Thu Jan 20, 2011 10:46 am
Re: Rangpur Higher Secondary 2011/3
THE INTERVAL OF fg should be [8,6]
Last edited by Mehfuj Zahir on Thu Feb 03, 2011 2:38 am, edited 1 time in total.
 leonardo shawon
 Posts: 169
 Joined: Sat Jan 01, 2011 4:59 pm
 Location: Dhaka
Re: Rangpur Higher Secondary 2011/3
$3<f<1$ and $2<g<4$
if $f=2.90$ and $g=1.90$ their multiple $fg$ will give a positive answer!!!
thats why $6<fg<4$
if $f=2.90$ and $g=1.90$ their multiple $fg$ will give a positive answer!!!
thats why $6<fg<4$
Ibtehaz Shawon
BRAC University.
long way to go .....
BRAC University.
long way to go .....

 Posts: 78
 Joined: Thu Jan 20, 2011 10:46 am
Re: Rangpur Higher Secondary 2011/3
if one of them is negative then?first time i was wrong the ans is (8,6)
Re: Rangpur Higher Secondary 2011/3
It's two ranges of $f$ and $g$ .It doesn't mean that if $f$ is $3$ then $g$ is $2$.leonardo shawon wrote:$3<f<1$ and $2<g<4$
if $f=2.90$ and $g=1.90$ their multiple $fg$ will give a positive answer!!!
thats why $6<fg<4$
Please read Forum Guide and Rules before you post.
Use $L^AT_EX$, It makes our work a lot easier!
Nur Muhammad Shafiullah  Mahi
Use $L^AT_EX$, It makes our work a lot easier!
Nur Muhammad Shafiullah  Mahi
 leonardo shawon
 Posts: 169
 Joined: Sat Jan 01, 2011 4:59 pm
 Location: Dhaka
Re: Rangpur Higher Secondary 2011/3
i got that later. My mistake! Sowry
Ibtehaz Shawon
BRAC University.
long way to go .....
BRAC University.
long way to go .....