Answer:
11.42 boxes
Step-by-step explanation:
For the first box bought, there is a 100% chance of getting a unique toy (since you still don't have any). E₁ = 1.
After that, there is a 4 in 5 chance of getting a unique toy from the next box, the expected number of boxes required is:

For the next unique toy, there is now a 3 in 5 chance of getting it:

Following that logic, there is a 2 in 5 chance of getting the 4th unique toy:

Finally, there is a 1 in 5 chance to get the last unique toy:

The expected number of boxes to obtain a full set is:

0.7(5x+15)=2.9 -(x+3)
3.5x+10.5=2.9-x-3
3.5x+10.5= -0.1- x
4.5x= -10.6
x= -2.3555...
Check:
0.7(5(-2.3555...) +15) = 2.9 -(x+3)
2.2555... = 2.2555...
Answer:
Step-by-step explanation:
3.14(pi) X 6 ^2 =
3.14*6 = 18.84
3.14x6^2 =36
your final answer is : B. : 36
Answer:
Area is measured in "square" units. The area of a figure is the number of squares required to cover it completely, like tiles on a floor. Area of a square = side times side. Since each side of a square is the same, it can simply be the length of one side squared.
Step-by-step explanation: hope this helps
646/3=x
To check it: x*3 should =646