Answer: Observational study
Step-by-step explanation:
The study illustrated in the question is an observational study. It is referred to as an observational study, because in this case, the price of the individual cereals us not being controlled by the students. They've no control over it.
If it was an experiment, there'll have been a control group and the students will have control over the price. Also, the sampling methods used here is a systematic random sampling.
Answer:
Step-by-step explanation:
1) Split the second term in 
into two terms.
1 - Multiply the coefficient of the first term by the constant term.
2 - Ask: Which two numbers add up to 2 and multiply to -35?
7 and -5.
3 - Split 2x as the sum of 7x and -5x.
2) Factor out common terms in the first two terms, then in the last two terms.
3) Factor out the common term x+1.
4) Solve for x.
1 - Ask: When will (x+1)(7x-5) equal zero?
When x + 1 0 or 7x-5=0
2 - Solve each of the 2 equations above.
Answer:
45
Step-by-step explanation:
Replace x with -1, and y = 9
Therefore, (x²y)/-7 becomes (-1² · 9)/-7
-1² is just 1, and 1 × 9 is just equal to 9, so your final answer is -9/7.
Answer:
<h3>Car A</h3>
- Initial price = $30000
- Initial depreciation = 20%
- Further yearly depreciation = $2000
<u>The equation to reflect the above:</u>
- A(t) = 30000 - 0.2*30000 - 2000t ⇒
- A(t) = 24000 - 2000t
<h3>Car B</h3>
- Initial price = $25000
- Initial depreciation = 10%
- Further yearly depreciation = $1500
<u>The equation to reflect the above:</u>
- B(t) = 25000 - 0.1*25000 - 1500t ⇒
- B(t) = 22500 - 1500t
