Question

(8.5H)Which situation represents 1 point
a proportional relationship?
The cost of purchasing hay for $26 a
bale with a delivery charge of $30.
The cost of purchasing baby chicks at
$4.50 per chick
The cost of purchasing fencing at $29
a linear foot with an installation fee of
$300.
The cost of renting a backhoe for $79
per hour with a non-refundable deposit
of $300.

Answer 1

The cost of purchasing baby chicks at  $4.50 per chick represents proportional relationship

Solution:

in a proportional relationship, one variable is always a constant value times the other.

y = kx

Where, k is a constant

Option 1

The cost of purchasing hay for $26 a  bale with a delivery charge of $30

Cost = $ 26 a bale + 30

This does not forms a proportional relationship

Option 2

The cost of purchasing baby chicks at  $4.50 per chick

Let "x" be the number of chicks

Therefore,

$cost = 4.50 \times x$

Thus, this forms a proportional relationship

Option 3

The cost of purchasing fencing at $29  a linear foot with an installation fee of  $300

cost = $ 29 a linear foot + 300

This does not forms a proportional relationship

Option 4

The cost of renting a backhoe for $79  per hour with a non-refundable deposit  of $300

cost = $ 79 per hour + 300

This does not forms a proportional relationship