9514 1404 393
Answer:
a) average rate = (total distance)/(total time)
b) Rave = 2·R1·R2/(R1 +R2)
c) cheetah's average rate ≈ 50.91 mph
Step-by-step explanation:
a) Let AB represent the distance from A to B. Let t1 and t2 represent the travel times (in hours) on leg1 and leg2 of the trip, respectively. Then the distances traveled are...
First leg distance: AB = 70·t1 ⇒ t1 = AB/70
Second leg distance: AB = 40·t2 ⇒ t2 = AB/40
The average rate is the ratio of total distance to total time:
average rate = (AB +AB)/(t1 +t2)
average rate = 2AB/(AB/70 +AB/40) = 2/(1/70 +1/40) = 2(40)(70)/(70+40)
average rate = 560/11 = 50 10/11 . . . mph
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No equations are given, so we cannot compare what we wrote with the given equations. In each step of the solution, we have used the rules of algebra and equality.
b) For two rates over the same distance (as above), the average is their harmonic mean:
average rate = 2r1·r2/(r1+r2)
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c) The cheetah's average rate was 50 10/11 mph ≈ 50.91 mph.
Answer: 21
Step-by-step explanation:
we have two simple equations:
1) 70=100%
2) x=30%
where left sides of both of them have the same units, and both right sides have the same units, so we can do something like that:
70/x=100%/30%
6. Now we just have to solve the simple equation, and we will get the solution we are looking for.
7. Solution for what is 30% of 70
70/x=100/30
(70/x)*x=(100/30)*x - we multiply both sides of the equation by
70=3.33333333333*x - we divide both sides of the equation by (3.33333333333) to get x
70/3.33333333333=x
The fore, the answer is 21
2 / 3 of 4 = ( 2 x 4 ) / 3 = 8 / 3 ;
Joe is positive 986 yards
Ziggy is negative 118 yards
the total difference is 986 +118 = 1,104 yards
1/3 has the greatest value
