Answer:
b. Engine oil E will cause a significant improvement is gas mileage.
Step-by-step explanation:
The research was conducted with the random vehicles who were introduced with Engine oil E. When compared with engine oil E and the generic oil the vehicle that uses engine oil E performed better. The gas mileage of such vehicles improved significantly as compared to other vehicles who received generic oil.
3x + 40 + x = 180
-40. -40
——————————-
4x. 140
—. ——-
4. 4
x = 35
First we distribute

into

and

.


That makes the left side of the equation

Now we subtract

from

, which makes

Now the equation is

Our goal is to isolate

, so we both sides by 30
That will make the equation

We multiply -1 on both sides of the equation:

Finally we simplify

, which makes
So the answer is
Answer:
Step-by-step explanation:
<u>This is an AP with:</u>
- The first term a₁ = 12
- Common difference d = 3
- Number of terms n = 40
<u>Number of the seats:</u>
- Sₙ = 1/2*n(a₁ + aₙ) = 1/2n(2a₁ + (n - 1)d)
- S₄₀ = 1/2*40(12*2 + 39*3) = 2820 seats
<u>Formula of nth term:</u>
- aₙ = a₁ + (n - 1)d
- aₙ = 12 + (n - 1)*3 = 12 + 3n - 3 = 3n + 9
- aₙ = 3n + 9