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
The answer is x equals 2.
Answer:
Strong Negative
Step-by-step explanation:
We already know that the answer is between c and d because the correlation coefficient negative.
We just have to figure out whether it is strong or weak.
In general, anything between -.7 and -1 is considered to have a strong correlation. -.8 is in between -.7 and -1 therefore the correlation is best described as strong negative.
Area of a trapezoid
1/2(a+b)(h) where a and b are the parallel sides and h is the height.
a = 12.9, b = 8.6, h = 6.4
A = 1/2(12.9 + 8.6)(6.4) = 68.8 cm²
Answer:
the answer is 16
Step-by-step explanation:
I had type into a calculator
