Answer:
k = 7.4
y = 133.2
Explanation:
To find the value of y when x= 18 we must first find the relationship between them
The statement
y varies directly as x is written as

where k is the constant of proportionality
when y = 37
x = 5
Substitute the values into the above formula and solve for k
That's
37 = 5k
Divide both sides by 5
k = 7.4
So the formula for the variation is
y = 7.4x
When x = 18
y = 7.4(18)
We have the answer as
y = 133.2
Hope this helps you