SOLUTION: Bill wastes 9 hours and receives a 60% on an Algebrat test. How many hours did Bill waste if he receives a 90%? Assume time wasted is inversely proportional to an Algebra test grad

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Question 1132400: Bill wastes 9 hours and receives a 60% on an Algebrat test. How many hours did Bill waste if he receives a 90%? Assume time wasted is inversely proportional to an Algebra test grade.
Found 2 solutions by josgarithmetic, ikleyn:
Answer by josgarithmetic(39620) About Me  (Show Source):
You can put this solution on YOUR website!
60% means 0.6.
90% means 0.9.

Inverse variation wanted, so for time x "wasted" and k proportionality constant, score y,

0.6k=1%2F9
k=1%2F%280.6%2A9%29
k=1%2F5.4
k=5%2F27

Model can be highlight_green%281%2Fx=k%2Ay%29.


If score were 0.9, then
x=1%2F%28k%2A0.9%29

x=27%2F%285%2A0.9%29

x=27%2F4.5
x=6----------wasted 6 hours

Answer by ikleyn(52802) About Me  (Show Source):
You can put this solution on YOUR website!
.

One can consider the condition as absurdist, because the greater work was done faster.


But I entirely agree with this condition and find it very realistic, because the person who knows a subject better, will do  the work faster.