The expression which relates the total time taken and the time taken for the trip is [15s + 15(s+2)] / s² + 2s and 2.32 hours respectively.
<em>Travel time = distance ÷ speed </em>
<u>Second half of the trip</u> :
- <em>Distance covered = 15 miles</em>
<u>Time taken for second half of trip</u> :
Time taken = 15 / s
<u>First half of the trip</u> :
- <em>Speed = s + 2 mph </em>
<u>Time taken for first half of trip :</u>
Time taken = 15 / (s+2)
<u>Total time taken :</u>
<em>First half + second half</em>
15/(s+2) + 15/s = [15s + 15(s+2)] / s² + 2s
B)
If s = 12
<em>Substitute s = 12 into the expression</em> :
[15(12) + 15(12+2)] / 12² + 2(12)
[180 + 210] / 144 + 24
390 / 168
= 2.32 hours
Therefore, the total time taken is 2.32 hours.
Learn more : brainly.com/question/18796573
Answer:
2000
Step-by-step explanation:
diameter of an average cell= 1 x 10^-5 mm
diameter of a pin head= 2 x 10^-2
number of body cells that would fit on the pin head=2 x 10^-2 ÷ 1 x 10^-5
=2000 body cells
Answer:
11+2n
Step-by-step explanation:
Arithmetic sequence=a+(n-1)d
a=first number
n=nth term
d=difference
a=9
n=?
d=-2
So let's solve
9+(n-1)(-2)
9+(2n+2)
9+2n+2
Collect like terms
9+2+2n
11+2n
So the nth term is 11+2n
As with any linear equation of this sort, divide by the coefficient of the variable.
.. 470 h = 3008
.. (470 h)/470 = 3008/470
.. h = 3008/470 = 6.4
