Let x be number of black markers
4.5x + 2x3.25x + 3x1.98x = 284.24
16.94x = 284.24
x = 16.78 = 17
The person bought 17 black pens, 34 red and 51 green
Assuming you mean 2x-8y=7, we can start by multiplying the first equation by -2 and adding it to the second (to cross out the x), resulting in -18y=-5. After that, we can divide both sides by -18, resulting in y=5/18. Next, plugging that into 4x-2y=9, we have 4x-10/18=9. Adding 10/18 to both sides, we get 4x=9+10/18. After that, we can divide both sides by 4, resulting in x=(9+10/18)/4=
Answer:
Option B)

Step-by-step explanation:
We are given the following in the question:
Hypothesis:
The doctors and u=instructor claims that practicing yoga reduces blood pressure and hence is beneficial to people.
Population mean, μ = 140 mm
Sample mean,
= 139 mm
Sample size, n = 51
Sample standard deviation, s = 5 mm
Thus, we can design the null hypothesis and alternate hypothesis as

The null hypothesis states that the population have a blood pressure of 140 mm. The alternate hypothesis states that yoga reduces the blood pressure and the sample has a blood pressure less than 140 mm.
Thus, the correct answer is
Option B)

1st ring=$50
2nd ring=$37.50
3rd ring=$25
$50+$37.50+$25 =$112.50 total cost before tax
$112.50 X 1.08=$121.5 total cost and tax
3 X $50 X 1.08=$162 total cost without discount deal
$162 - $121.50 =$40.50 savings