Answer:
1. I would think it would be a appropriate to use a normal model to figure this out because sometimes when you are using stuff online you can get the same number like 20 times in a row, whereas, if you use a real dice, you most likely won't roll the same number 20 times.
2. { sorry two doesn't make sense }
C) (0.85 + x/100)(250+145) does not give the correct answer.
Explanation
A) works; adding the two costs together is 250+145=395. We multiply this by 0.85 because 100%-15%=85%=0.85. We also have x% tax, which is represented by x/100, added to 100% of the value, or 1.00. Altogether this gives us
395(0.85)(1+x/100) = 395(0.85 + (0.85x/100)) = 395(0.85) + 395(0.85x/100)
= 395(0.85) + 395(0.0085x)
B) works; we have 250+145 for the original price; we have 85% = 0.85 of the value; we also have 100% + x%, which is (100+x)/100.
C) does not work; (0.85+x/100)(395) does not take into consideration that you are finding the tax after taking the 85%. This will simplify out to
0.85*395 + (x/100)(395) = 335.75 + 395x/100 = 335.75 + 3.95x, which is too much.
D) works; simplifying the expression from A, we have 395(0.85) + 395(0.0085x) = 335.75 + 3.3575x.
Given:
The system of equation is


To find:
The solution of given system of equations.
Solution:
The slope intercept form of a line is

Where, m is slope and b is y-intercept.
Write the given equation in slope intercept form.
The first equation is


...(i)
Here, slope is
and y-intercept is 4.
The second equation is
...(i)
Here, slope is
and y-intercept is -4.
Since the slopes of both lines are same but the y-intercepts are different, therefore the given equations represent parallel lines.
Parallel lines never intersect each other. So, the given system of equation has no solution.
Hence, the correct option is B.
7978 years
Step-by-step explanation:
A = A02^(-t/hl)
where hl = half-life.
Dividing both sides by A0 and taking the logarithm, we get
ln(A/A0) = -(t/hl)ln2
or solving for t,
t= -(hl)ln(A/A0)/ln2
note that A/A0 = 0.38
t = -(5715 yrs)[ln(0.38)/ln2]
= 7978 years
A+b is less than or equal to 50