The probability of choosing a correct answer = 1/5
The probability of choosing a wrong answer = 4/5
Scores received on correct answer = +3
Scores received on wrong answer = -1
Scores on blank answer = 0
The average scores, in long run will be equal to the expected value. The expected value E, in this case will be:
Thus, in long run, the student will score -0.2 points on average.
Answer:
(4,3)
Step-by-step explanation:
Given
x^2+y^2=25
x-y^2=-5
In order to solve the equations, from equation 2 we get
-y^2= -5-x
y^2=5+x
Putting the value of y^2 in equation 1
x^2+5+x=25
x^2+5-25+x=0
x^2+x-20=0
x^2+5x-4x-20= 0
x(x+5)-4(x+5)=0
(x+5)(x-4)=0
So
x+5=0 x-4=0
x=-5 x=4
Now for x=-5
x^2+y^2=25
(-5)^2+y^2=25
25+y^2=25
y^2=25-25
y^2=0
so Y=0
And for x = 4
x^2+y^2=25
(4)^2+y^2=25
16+y^2=25
y^2=25-16
y^2=9
y= ±3
So the solution to the system of equations is
(-5,0) , (4,3), (4,-3)
The only solution that belongs to first quadrant is (4,3)
Answer:
the answer is 4
Step-by-step explanation:
hope this helps!
Answer:
Jess used 40 blocks in total.
Step-by-step explanation:
First stack: 8 blocks
Second stack: First stack + 4 = 8 + 4 = 12 blocks
Third stack: Second stack + 8 = 12 + 8 = 20 blocks
Total number of blocks: First stack + Second stack + Third stack = 8 + 12 + 20 = 40 blocks