Question

Please help me with this

Answer 1

So since 2/5 of the washing machines have been sold that means 3/5 remain in the store 
 
first find the number of washing machines that were in the store before any were sold 

X is the number of washing machines in the store before selling

18=(3/5)X

18/(3/5)=X
X=18*(5/3)
X=30

so at the beginning there were 30 machines

then multiply the percent sold (2/5) by the number at beginning to find the number sold

(2/5)*30=12

so 12 machines were sold

to find the cost per machine divide the total price by number of machines sold so 

$3840/12= $320 

so the answer is $320 per machine