Final answer:
The value of f, when g equals 3, is found by substituting g into the direct proportionality equation f = 6g, yielding a value of f = 18.0.
Step-by-step explanation:
The student is asking for the value of f when g = 3, given the direct proportionality equation f = 6g. To calculate this, we simply substitute 3 into the equation for g:
f = 6 × 3
Solving this, we get:
f = 18
Therefore, the value of f when g is 3 is 18, to one decimal place it is 18.0.