Inverse Supply

The inverse supply curve represents the price as a function of the quantity supplied.

Example

The supply for cookies follows the following equation: `Q_s = 10 + 2P`.

Solving for P:

$$ \begin{align*} Q_s &= 10 + 2P \\ 2P &= Q_s - 10 \\ P &= \frac{Q_s - 10}{2} \end{align*} $$ The inverse supply is `P = \frac{Q_s - 10}{2}`

Question

The supply for bananas follows the equation `Q_s = 340 + 17 P`.

Find the inverse supply function.

Determine the price of bananas when the quantity supply is 2720.

Let's transform the supply function into the inverse supply function.

$$ \begin{align*} Q_s &= 340 + 17 P \\ 17 P &= Q_s - 340 \\ P &= \frac{340 - Q_s}{17} \end{align*} $$

The inverse supply function is `P = \frac{340 - Q_s}{17}`.

If the quantity supplied is 2720, then

$$ P = \frac{340 - 2720}{17} = 140 $$

The price producers get for a banana is $140.