Question

in a small town, 10 residents move to new cities each year for 3 years. the equation below is written to represent the situation: (-10)·3 = -30 which description best explains the meaning of -30 in the equation? a -30 residents leave the town. b there are -30 residents in the town. c the change in the number of residents per year is -30. d the total change in the number of residents in the town due to people moving away is -30.

Explanation:

• Option A: Saying “$-30$ residents leave” is incorrect grammar as we can't have a negative count of people leaving in that phrasing.
• Option B: There can't be $-30$ residents in a town. The number of residents is a non - negative quantity in a real - world context.
• Option C: The change per year is $- 10$ (since 10 residents leave each year), not $-30$.
• Option D: Since 10 residents leave each year for 3 years, the total change (using the formula $(-10)\times3=-30$) represents the total decrease in the number of residents due to people moving away.

Answer:

D. The total change in the number of residents in the town due to people moving away is $-30$.