SOLUTION: The average (arithmetic mean) of 6,21,x and y is 13, where x and y are integers with a product of 100. What is the value of x?
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Question 885834: The average (arithmetic mean) of 6,21,x and y is 13, where x and y are integers with a product of 100. What is the value of x? Answer by dkppathak(439) (Show Source):
You can put this solution on YOUR website! The average (arithmetic mean) of 6,21,x and y is 13, where x and y are integers with a product of 100. What is the value of x?
solution
airthmatic mean = 6+21+X+Y/4= 13 (given)
6+21+X+Y= 52
X+Y=52-27
X +Y =25 (1)
Xy =100 (2)(second condition given)
X +Y =25
X=Y-25 by substituting in (2)
X Y =100
(y-25)y =100
Y^2 -25y =100
Y^2-25Y -100 =0 by factorization
Y^2-20Y-5Y-100=0
(y-5)(Y-20)=0
y=5 oy y =20
than X=20 or x=5
Answer X=20 and Y=5 or X=5 and Y=20
