Question

(a) hong’s test score average decreased by 3 points this semester. write a signed number to represent this change in average. (b) keith lost 100 dollars from his pocket. write a signed number to represent this change.

Explanation:

Part (a)

Step 1: Understand the change

A decrease in test score average means a negative change. The amount of decrease is 3 points.

Step 2: Represent with a signed number

To represent a decrease of 3 points, we use the signed number $-3$.

Part (b)

Step 1: Understand the change

Losing money means a negative change in the amount of money Keith has. The amount lost is 100 dollars.

Step 2: Represent with a signed number

To represent a loss of 100 dollars, we use the signed number $-100$.

Answer:

(a) $\boldsymbol{-3}$
(b) $\boldsymbol{-100}$