Question

Which of the following table DONOT represent/s function ?

• A.

  INPUT$\left(X\right)$	OUTPUT$\left(Y\right)$
  $28$	$23$
  $32$	$20$
  $43$	$41$
  $47$	$49$

• B.

  INPUT$\left(X\right)$	OUTPUT$\left(Y\right)$
  $102$	$101$
  $105$	$103$
  $107$	$111$
  $108$	$106$

• C.

  COLOR	GADGETS
  RED	EARPHONES
  GREEN	BOTLE
  RED	LEDTV
  GREEN	TABLET

• D.

  SHOES BRAND	PRICES(in $)
  Nike	$3000$
  Reebok	$2900$
  Nike	$2599$
  Puma	$2499$

Answer 1

Answer: (C), (D)

SHOES BRAND	PRICES(in $)
Nike	$3000$
Reebok	$2900$
Nike	$2599$
Puma	$2499$

We know, If Input and Output are shown by a table, then it will be function from input to output only if each and every input value is related to the different output value in the table.
In option$\left(a\right)$ and $\left(b\right)$ we can see all the input values are related to different output values or we can say there in no repeatition of any value in input value column. Hence, Both tables in option$\left(a\right)$ and $\left(b\right)$ represent function.
Now, in options $\left(c\right)$ red color is associated to two different gadgets and green color also associated to two different gadgets hence, this table does not represent the function.
Similarly, in option $\left(d\right)$ Nike brand is associated to two different prices hence this table also doesnot represent the function.