Question

a car increases, then decreases, its speed. which table could represent the speed of the car?
time (min) 5 6 7 8 9
speed (mph) 45 43 41 42 43
time (min) 5 6 7 8 9
speed (mph) 45 47 49 48 47
time (min) 5 6 7 8 9
speed (mph) 45 45 45 43 41
time (min) 5 6 7 8 9
speed (mph) 45 43 41 41 41

Explanation:

Step1: Analyze the first table

The speed values are \(45,43,41,42,43\). The speed first decreases (\(45\) to \(43\) to \(41\)) and then increases (\(41\) to \(42\) to \(43\)), which is not “increase - then decrease”.

Step2: Analyze the second table

The speed values are \(45,47,49,48,47\). The speed first increases (\(45\) to \(47\) to \(49\)) and then decreases (\(49\) to \(48\) to \(47\)), which matches “increase - then decrease”.

Step3: Analyze the third table

The speed values are \(45,45,45,43,41\). The speed is constant (\(45\)) for the first three time - points and then decreases, which is not “increase - then decrease”.

Step4: Analyze the fourth table

The speed values are \(45,43,41,41,41\). The speed is decreasing (\(45\) to \(43\) to \(41\)) and then remains constant, which is not “increase - then decrease”.

Answer:

The second table (with speed values \(45,47,49,48,47\))