b Use a conversion factor to express Tabitha's speed in miles per minute.
C
c Use a conversion factor to express Tabitha's speed in kilometers per hour.
A
a False.
B
b True.
C
c True.
a We want to determine if, during a 5-kilometer run, Tabitha's speed was 4.8 miles per hour. To do so we will first use a conversion factor to express her speed in kilometers per hour. Recall that 1h=60min.
0.08 kmmin* 60min/1h=4.8 kmh
Now we will use a second conversion factor to express her speed in miles per hour. Recall this time that 1mi≈ 1.61km.
4.8 kmh* 1mi/1.61km ≈ 3 mih
We found that her speed was about 3 miles per hour. Thus, the statement that says her speed was 4.8 miles per hour is false.
b We want to determine if, during a 5-kilometer run, Tabitha's speed was about 0.05 miles per hour. To do so, will use a conversion factor to express her speed in miles per minute. Recall that 1mi≈ 1.61km.
0.08 kmmin* 1mi1.61km ≈ 0.05 mimin
We found that her speed was about 0.05 miles per minute. Thus, the statement is true.
c We want to determine if, during a 5-kilometer run, Tabitha ran faster than 4 kilometers per hour. To do so we will use a conversion factor to express her speed in kilometers per hour. Recall that 1h= 60min.
0.08 kmmin * 60min1h= 4.8 kmh
We found that her speed was 4.8 kilometers per hour. Therefore, she ran faster than 4 kilometers per hour and thus the statemnt is true.
