Answer:
B
Step-by-step explanation:
trust meh
Answer:
5/6
Step-by-step explanation:
9/30 + 16/30 = 25/30 = 5/6
Answer:
40
Step-by-step explanation:
Let n represent the integer. Then the increase can be written as ...
n + (-12) = 28
We can add 12 to both sides of this equation:
n + (-12) + (+12) = 28 +12
n + 0 = 40 . . . . . . -12 and 12 total to zero; 28 and 12 total to 40.
n = 40
The integer is 40.
Ax^2+bx=c
REMEMBER THIS
ok
first, make sure that a is 1
done
now take 1/2 of b and square it
-18/2=-9, (-9)^2=81
add that to both sides
x²-18x+81=19+81
x²-18x+81=99
factor perfect square
(x-9)²=100
square root both sides
don't forget positive and negative root
x-9=10
x-9=-10
ad 9 to both sides
x=19
x=-1
answer is -1; 19
2nd choice is answer
Answer:
Mean = 1.57
Variance=0.31
Step-by-step explanation:
To calculate the mean and the variance of the number of successful surgeries (X), we first have to enumerate the possible outcomes:
1) Both surgeries are successful (X=2).
2) Left knee unsuccessful and right knee successful (X=1).
3) Right knee unsuccessful and left knee successful (X=1).
4) Both surgeries are unsuccessful (X=0).
Then, the mean can be calculated as the expected value:
The variance can be calculated as:
