A student has a​ one-dollar bill, a​ five-dollar bill, and a​ ten-dollar bill in a box. The student selects a bill from the box 49 times and selects the one-dollar bill 20 times. What formula should be used to calculate the experimental​ probability? What is the experimental probability of selecting the one-dollar ​bill? What is the theoretical probability for selecting the one-dollar bill?

r / n

62.2%

33.3%

Step-by-step explanation:

The formula to be used is to divide the number of times that it came out by the total number of times the event was repeated because this was the experiment that was carried out, therefore this would be the experimental formula:

r / n

r = specific event (that the 10 dollar bill comes out)

n = total events

To calculate, we know the previous values r = 28 and n = 45, we replace:

28/45 = 0.622

that is, 62.2% is the experimental probability.

To calculate the theoretical propagation, we know that there are 3 types of banknotes and we want 1 of those 3 types to appear, therefore:

1/3 = 0.333

Ie 33.3% is the theoretical probability

a.   we have two

lines:   y = 4-x   and  

y = 8-x^-1

given two simultaneous equations that are both to be

true, then the solution is the points where the lines cross. the intersection is

where the two equations are equal. therefore the solution that works for both

equations is when

4-x = 8-x^-1

this is where the two lines will cross and that is the

common point that satisfies both equations.

b.   4-x = 8-x^-1

  x           4-x       8-x^-1

-3           7        

8.33

-2           6         8.5

-1           5         9

  0           4        

-

  1           3        

7

  2           2        

7.5

  3           1         7.67

the table shows that none of the x values from -3 to 3 is

the solution because in no case does

4-x = 8-x^-1

to find the solution we need to rearrange the equation to

find for x:

4-x = 8-x^-1

multiply both sides with x:

4x-x^2 = 8x-1

x^2+4x-1=0

x= -4.236, 0.236

therefore there are two points that satisfies the

equation.

find y:  

x=-4.236

y = 4-x   = 4 – (-4.236)

= 8.236

y = 8-x^-1 =   .236)^-1

= 8.236

x=0.236

  y = 4-x   = 4 – (0.236) = 3.764

y = 8-x^-1 =   8-(0.236)^-1

= 3.764

thus the two lines cross at 2 points:

(-4.236, 8.236) & (0.236, 3.764)

c.   to solve

graphically the equation 4-x = 8-x^-1

we would graph both lines: y = 4-x   and   y

= 8-x^-1

the point on the graph where the lines cross is the

solution to the system of equations.

just graph the points on part b on a cartesian coordinate

system and extend the two lines.   the

solution is, as stated, the point where the two lines cross on the graph.

step-by-step explanation:

mark brainliest!