3.939x10^-6
That should be right.
TRUE............................
21/50; 420/1000=42/100 simplify it and it is 21/50
Cost of installation fee is $120.
Step-by-step explanation:
Let,
Monthly fee = x
Installation fee = y
According to given statement;
6x+y=594 Eqn 1
11x+y=989 Eqn 2
Subtracting Eqn 1 from Eqn 2

Putting x=79 in Eqn 1

Cost of installation fee is $120.
Keywords: Linear equations, subtraction
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