Answer:
13
Step-by-step explanation:
We need to write our answer in exponential form. Ask yourself the question, "What times itself 3 times will give you 2197?" Your answer is
. This will go inside of your cube root. You now have
. Since there's a power of 3 and a cube root, those cancel each other out, and your answer is 13.
Answer:
About 1.23 standard deviation above the mean
Step-by-step explanation:
From what we have here, we need to calculate the difference between the given value and the mean and divide by the standard deviation
That would be through calculating the z score as follows;
z-score = (x - mean)/SD
where x is the given value
z-score = (87-71)/13 = 1.23
Since the score is bigger than the mean, the correct choice here is that the score is about 1.23 standard deviation above the mean
Answer:
I don't get the "number of 40" part, but here's my best shot!
3(40x)-5
Step-by-step explanation:
Answer:No
Step-by-step explanation:
Let's define variables:
s = original speed
s + 12 = faster speed
The time for the half of the route is:
60 / s
The time for the second half of the route is:
60 / (s + 12)
The equation for the time of the trip is:
60 / s + 60 / (s + 12) + 1/6 = 120 / s
Where,
1/6: held up for 10 minutes (in hours).
Rewriting the equation we have:
6s (60) + s (s + 12) = 60 * 6 (s + 12)
360s + s ^ 2 + 12s = 360s + 4320
s ^ 2 + 12s = 4320
s ^ 2 + 12s - 4320 = 0
We factor the equation:
(s + 72) (s-60) = 0
We take the positive root so that the problem makes physical sense.
s = 60 Km / h
Answer:
The original speed of the train before it was held up is:
s = 60 Km / h