SOLUTION: pls help me to answer: z is directly proportional to x and inversely to the square of y. what is the percent of z if x is increased by 20% and y is decreased by 40%?

Question 1134024: pls help me to answer: z is directly proportional to x and inversely to the square of y. what is the percent of z if x is increased by 20% and y is decreased by 40%?
Found 2 solutions by Alan3354, MathLover1:
Answer by Alan3354(69443) (Show Source): You can put this solution on YOUR website!
z is directly proportional to x and inversely to the square of y. what is the percent of z if x is increased by 20% and y is decreased by 40%?
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z = k*x/y^2
z2 = k*(1.2x)/(0.6y)^2 = z*(1.2/0.36) = 10z/3
An increase of 7z/3 = 233.33...%

Answer by MathLover1(20850) (Show Source): You can put this solution on YOUR website!

Given
Hence assuming proportionality constant as AMP Parsing Error of []: Invalid expression '': syntax error at /home/ichudov/project_locations/algebra.com/templates/Algebra/Expression.pm line 203. . 1.
increase by % and decreases by %
Hence value becomes:

Change in value
=
=

Increase in % =
=%

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