Answer:
36 mph
Step-by-step explanation:
The appropriate relations are ...
time = distance/speed
speed = distance/time
Suppose the race has a total length of 360 miles. Then half the race is 180 miles.
The cyclist's time on the first half is (180 mi)/(30 mi/h) = 6 h.
The cyclist's time on the second half is (180 mi)/(45 mi/h) = 4 h.
The total time is 10 h for the total distance of 360 mi, so the average speed is ...
(360 mi)/(10 h) = 36 mi/h
_____
The length of the race doesn't matter. The above numbers make the math convenient. The average is computed from ...
1/((1/2)/30 + (1/2)/45) = 2/(1/30 +1/45) = 2·30·45/(30+45) = 36
This is the <em>harmonic mean</em> of the numbers 30 and 45.
Answer:
a > -9
subtract 6 from both sides to get 2/3 a > -6. Then multiply both sides by 3 to get 2a > -18. Last, divide both sides by 2 to get your answer: a > -9
Answer:
B 2/3
Step-by-step explanation:
Answer:
A
Step-by-step explanation:
Madison created two functions.For Function A, the value of y is two less than four times the value of x.
The table below represents Function B.
-3,-9
-1,5
1,-1
3,3
In comparing the rates of change, which statement about Function A and Function B is true?
A.
Function A and Function B have the same rate of change.
B.
Function A has a greater rate of change than Function B has.
C.
Function A and Function B both have negative rates of change.
D.
Function A has a negative rate of change and Function B has a positive rate of change.
C is correct
