The relation between demand $q$ and price $p$ is given by $q(p) = \dfrac{210}{p}$. Determine the avereage change in demand if the price decreaes from $p=10$ to $p=7$.
Antwoord 1 correct
Correct
Antwoord 2 optie
$3$.
Antwoord 2 correct
Fout
Antwoord 3 optie
$\dfrac{9}{10}$.
Antwoord 3 correct
Fout
Antwoord 4 optie
$\dfrac{9}{7}$.
Antwoord 4 correct
Fout
Antwoord 1 optie
$-3$.
Antwoord 1 feedback
Correct: The difference quotient is $\dfrac{\Delta q}{\Delta p} = \dfrac{q(7)-q(10)}{7-10} = \dfrac{30-21}{-3} = -3$.
Go on.
Go on.
Antwoord 2 feedback
Wrong: Pay attention to the order of $q(p)$ and $q(p+\Delta p)$ in the nominator or check how you determined $\Delta p$.
See also Example 1.
See also Example 1.
Antwoord 3 feedback
Antwoord 4 feedback