Choose the best answer.

Question

Scientists are monitoring a whale's weight by observing its weight change once a week, over a 4 week period. How much has the whale's weight changed over the entire 4 weeks?


A graph showing the differences in a whales weight over the course of four weeks. Week 1, weight change (in pounds) -2.1. Week 2, weight change (in pounds) +0.3. Week 3, weight change (in pounds) -1.7. Week 4, weight change (in pounds) -0.4.

Question 5 options:

4.1 pounds

–0.1 pounds

0.3 pounds

–3.9 pounds

Answer 1

The whale's weight change over the entire 4 weeks can be calculated by summing up the weight changes for each week:

Week 1: -2.1 pounds
Week 2: +0.3 pounds
Week 3: -1.7 pounds
Week 4: -0.4 pounds

Adding these values together, we get:
-2.1 + 0.3 - 1.7 - 0.4 = -3.9 pounds

Therefore, the whale's weight has changed by -3.9 pounds over the entire 4 weeks.