Difference between revisions of "1950 AHSME Problems/Problem 11"

(???)
 
m
Line 16: Line 16:
  
 
{{AHSME box|year=1950|num-b=10|num-a=12}}
 
{{AHSME box|year=1950|num-b=10|num-a=12}}
 +
 +
[[Category:Introductory Algebra Problems]]

Revision as of 13:27, 17 April 2012

Problem

If in the formula $C =\frac{en}{R+nr}$, $n$ is increased while $e$, $R$ and $r$ are kept constant, then $C$:

$\textbf{(A)}\ \text{Increases}\qquad\textbf{(B)}\ \text{Decreases}\qquad\textbf{(C)}\ \text{Remains constant}\qquad\textbf{(D)}\ \text{Increases and then decreases}\qquad\\ \textbf{(E)}\ \text{Decreases and then increases}$

Solution

Assume that the constants are positive, as well as $n.$

WLOG let $e,$ $R,$ and $r$ all equal $1.$ Then $C=\frac{n}{1+n}.$ We can see that as $n$ increases from $0,$ it slowly approaches $1.$ Therefore, $C$ $\boxed{\mathrm{(A)}\text{ }\mathrm{ Increases}.}$

If $r$ and $R$ were positive and $e$ was negative, then $C$ would decrease, for example.

See Also

1950 AHSME (ProblemsAnswer KeyResources)
Preceded by
Problem 10
Followed by
Problem 12
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
All AHSME Problems and Solutions