recipricol probelm... PLEASE HELP!
- Thread starter feenok
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- Apr 12, 2005
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Why is one posting this again?
One thing you can do is forget the concept of "cross multiply". In my view, the idea is far more trouble than it's worth.
n = the number we seek
1/n = it's reciprocal
n + 1/n = 52/12
I'm a little curious why 52/12 is in the problem statement. Why isn't it reduced?
n + 1/n = 52/12
Multiply by n
n<sup>2</sup> + 1 = (52/12)*n
Multiply by 12
12*n<sup>2</sup> + 12 = 52*n
See how neatly the fractions disappear through procedures that are NOT confusing? Solve that quadratic. I still wonder why we started with 52/12.
One thing you can do is forget the concept of "cross multiply". In my view, the idea is far more trouble than it's worth.
n = the number we seek
1/n = it's reciprocal
n + 1/n = 52/12
I'm a little curious why 52/12 is in the problem statement. Why isn't it reduced?
n + 1/n = 52/12
Multiply by n
n<sup>2</sup> + 1 = (52/12)*n
Multiply by 12
12*n<sup>2</sup> + 12 = 52*n
See how neatly the fractions disappear through procedures that are NOT confusing? Solve that quadratic. I still wonder why we started with 52/12.
Ohhh...didn't realise THAT was the "realm of you wonderment";tkhunny said:
I meant 52/12 has no sensible solution, but 51/12 does...
AND: any teacher in his right mind would show 51/12, not 17/4;
then he can "appear smarter than your average bear..." and yell at
his students: "DID YOU START BY REDUCING THE FRACTION?" :lol: