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
__
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)
__
c) The cheetah's average rate was 50 10/11 mph ≈ 50.91 mph.
The answer is the last one, the expression is already in the simplest form.
12.36% I think sorry if its wrong ;-;
The x represents how many songs Sabrina has because if you are saying Nicolas has three less than twice as many as her then you are doubling the amount of songs Sabrina has and you're subtracting 3 from that to get how many songs Nicolas has. Let's say Sabrina has 29 songs. Now we are trying to find out how many songs Nicolas has. 2x-3. 2(29) - 3. 58-3. Nicolas has 55 songs if Sabrina were to have 29. I really hope this helped :)
Answer:
Step-by-step explanation:
Another way to solve would be to distribute first:
22 = 2(x + 6)
22 = 2x + 12
Subtract 12:
22 - 12 = 2x - 12
10 = 2x
Divide by 2:
10 / 2 = 2x / 2
5 = x
