SOLUTION: A repairman purchased some washing machine motors for a total of $224. When the unit cost decreased by $4, he was able to buy one extra motor for the same total price. How many mot
Question 379546: A repairman purchased some washing machine motors for a total of $224. When the unit cost decreased by $4, he was able to buy one extra motor for the same total price. How many motors did he buy originally? Answer by mananth(16946) (Show Source):
You can put this solution on YOUR website! let the number of motors he bought be x
he paid $224
so he paid 224/x for each motor.
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(224/x) -4 is the reduced price.
he got (x+1) motors
((224/x)-4)(x+1)=224
((224-4x)/x)(x+1)= 224
(224-4x)(x+1)/x=224
multiply by x
(224-4x)(x+1)= 224x
224x+224-4x^2-4x=224x
re write
224x-224x+224 -4x^2-4x=0
4x^2+4x-224=0
/4
x^2+x-56=0
x^2+8x-7x-56=0
x(x+8)-7(x+8)=0
(x+8)(x-7)=0
x= 7
The number of motors he bought originally = 7
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m.ananth@hotmail.ca
