A bird goes from a lower location to a higher location at a rate of 4 meters per second. Which equation models the change in the bird's position at 60 seconds?
A. (-60)(-4) = -240
B. 60.4 = 240
C. 60(-4) = -240
D. 60(-4) = 240

The answer is C. 60(-4) = -240

Step-by-step explanation:

First, let's eliminate some of the choices. A doesn't make sense since negative times a negative equals positive. Secondly, how can 60.4 equal 240 when 60.4 is less than 240? Furthermore, D doesn't make sense since positive times a negative equals negative.

Here is a rule for you to remember:

When multiplying two integers with different signs, the product is always negative; when multiplying two integers with the same sign, the product is always positive.