In September, a sporting goods store offers a kayak for $378. Over the next four months, the store reduced the price of the kayak $15 each month. What is the price of the kayak at the end of four months?

$438

$363

$228

$318

At the end of the first month, the price of the kayak is $378 - $15 = $<<378-15=363>>363.

At the end of the second month, the price of the kayak is $363 - $15 = $<<363-15=348>>348.
At the end of the third month, the price of the kayak is $348 - $15 = $<<348-15=333>>333.
At the end of the fourth month, the price of the kayak is $333 - $15 = $<<333-15=318>>318.
So the price of the kayak at the end of four months is $318. Answer: \boxed{318}.

To find the price of the kayak at the end of four months, we need to subtract $15 each month for four months from the original price of $378.

First, we subtract $15 from $378 to get: $378 - $15 = $363.

Next, we subtract another $15 from $363 to get: $363 - $15 = $348.

Then, we subtract another $15 from $348 to get: $348 - $15 = $333.

Finally, we subtract a final $15 from $333 to get: $333 - $15 = $318.

Therefore, the price of the kayak at the end of four months is $318.