Question

The variable type and the correct relation between Running time ($a$) and Maintainance cost ($z$) is-

Running time ($a$)	3	7	11	15
Maintainance cost ($z$)	9	17	25	33

• A. $z$—Independent, $a$—Dependent and $z=3a+2$
• B. $z$—Independent, $a$—Dependent $z=2a+3$
• C. $z$—Dependent, $a$—Independent and $z=2a+3$
• D. $z$—Dependent, $a$—Independent and $z=3a+2$

Answer 1

The correct option is C $z$—Dependent, $a$—Independent and $z=2a+3$

From the table:

Running time ($a$)	3	7	11	15
Maintainance cost ($z$)	9	17	25	33

it can be observed,
$3\times 2+3=9$
$7\times 2+3=17$
$11\times 2+3=25$
$15\times 2+3=33$
hence,
$z=2a+3$
where '$z$' is dependent and '$a$' is independent.