Question

The vector u = 3224, 1429, 2275 gives the numbers of hamburgers, chicken sandwiches, and cheeseburgers, respectively, sold at a fast-food restaurant in one week. The vector v = 1.50, 2.50, 1.90 gives the prices (in dollars) per unit for the three food items. Find the dot product u · v. (Round your answer to two decimal places.) $

Answer 1

u.v = $12,731.

Explanation:

The dot product between two vectors, a and b, in which

a = (c,d,e)

b = (f,g,h)

Is given by the following formula

a.b = (c,d,e).(f,g,h) = cf + dg + eh.

In this problem, we have that:

u = (3224, 1429, 2275)

v = (1.50, 2.50, 1.90)

So

u.v = (3224, 1429, 2275).(1.50, 2.50, 1.90) = 3224*1.50 + 1429*2.50 + 2275*1.90 = $12,731.