Answer:
k = 2/5
Step-by-step explanation:
from the question , we have that Suppose y is directly proportional to x
mathematically'
y ∝ x
y = kx ................................................................. where k is the constant of proportionality
given that y = 8, x = 20 where k = ?
so from,
y = kx
we are going to make k the subject of the formula by getting rid of x away from k.
y = kx
divide both sides by x
y/x = kx/x
y/x = k
therefore k = y/x
k = 8/20
k = 2/5
therefore the value of k which is the constant of proportionality in this expression is given to be 2/5
