Question

the variables y and x have a proportional relationship, and y = 15 when x = 3.
what is the value of x when y = 4?
enter your answer in the box.

x =

0.8
5
1.25
20

Explanation:

Step1: Find proportionality constant $k$

Proportional relationship: $y = kx$. Substitute $y=15, x=3$:
$15 = 3k$
$k = \frac{15}{3} = 5$

Step2: Write full proportional equation

$y = 5x$

Step3: Solve for $x$ when $y=4$

Substitute $y=4$:
$4 = 5x$
$x = \frac{4}{5} = 0.8$

Answer:

0.8 (A. 0.8)