Full question :
Nthe first round of a card game, niki scored 20 points. then, she lost 10 points on one turn and an additional 25 points on her final turn. part a choose the number line that shows the change in niki’s score.
a. number line from -20 to 20. start at -20. count up by 5. 3 arrows are shown above the number line. 1st from 0 to -20, 2nd from -20 to -10 and 3rd from -10 to 15.
b. number line from -20 to 20. start at -20. count up by 5. 3 arrows are shown above the number line. 1st from 20 to 0, 2nd from 0 to -10 and 3rd from -10 to 15.
c. number line from -20 to 20. start at -20. count up by 5. 3 arrows are shown above the number line. 1st from 0 to 20, 2nd from 20 to -5 and 3rd from -5 to 5.
d. number line from -20 to 20. start at -20. count up by 5. 3 arrows are shown above the number line. 1st from 0 to 20, 2nd from 20 to 10 and 3rd from 10 to -15.
part b what is niki’s final score? enter your answer in the box. points
Answer:
d. number line from -20 to 20. start at -20. count up by 5. 3 arrows are shown above the number line. 1st from 0 to 20, 2nd from 20 to 10 and 3rd from 10 to -15.
Explanation:
The number line given run from -20 to +20 and so we record Niki's losses and wins using the negative numbers and positive numbers respectively. If Niki wins(scores 20 points) we add, that is a positive number on the number line. If Niki loses(loses 10 and 25 points) we subtract from her positive number using the negative values(points missed) on the number line. If we do this, Niki's value on the number line ends up at -15
To get Niki's final score, we calculate hence
+20-10-25 = -15 points