khalillulah
Junior Member
:salam2:
first of the algebra approach will not work though you will end up one equation and one expression. let say your total is 60
x=no. of boys
y=no. of girls
first equation will be
10x+y=45 if you start working from top to bottom
you can also get an expression for no. of boys if start working from bottom to top .
[60-y/5-3]/2.....(no. of boys) . the problem is you can't plug this expression in the above equation coz it is the same equation worked in a different way.
we can manipulate the first equation by looking for factors of 45
10x+y=45.... no. of boys multiplied by ten then you add no. of girls
factor out 10 from 45 will be (10 x 4)+5=45... is like no. of boys multiplied 10 then added no. of girls..........this is only true and possible if the original problem the no. of boys x 2 added 3 x by 5 then added no. of girls at last. notice i have remove the factor 3 x 5 by subtracting 15 from the total. also the no. of girls have to be less than 10
even the three digit is possible if the factor 20 but the no. of girls have to be less than 15. you see this is not a math problem coz some set of rules have satisfied first.
well i don't know the alogarithm method i like brother humblewun to explain.
hope makes some sense.
first of the algebra approach will not work though you will end up one equation and one expression. let say your total is 60
x=no. of boys
y=no. of girls
first equation will be
10x+y=45 if you start working from top to bottom
you can also get an expression for no. of boys if start working from bottom to top .
[60-y/5-3]/2.....(no. of boys) . the problem is you can't plug this expression in the above equation coz it is the same equation worked in a different way.
we can manipulate the first equation by looking for factors of 45
10x+y=45.... no. of boys multiplied by ten then you add no. of girls
factor out 10 from 45 will be (10 x 4)+5=45... is like no. of boys multiplied 10 then added no. of girls..........this is only true and possible if the original problem the no. of boys x 2 added 3 x by 5 then added no. of girls at last. notice i have remove the factor 3 x 5 by subtracting 15 from the total. also the no. of girls have to be less than 10
even the three digit is possible if the factor 20 but the no. of girls have to be less than 15. you see this is not a math problem coz some set of rules have satisfied first.
well i don't know the alogarithm method i like brother humblewun to explain.
hope makes some sense.