Answer:
Expected value =0.9
Standard deviation = 0.4359
Step-by-step explanation:
Let's use the formula to find expected value or mean.
Expected value =Σ x *P(x)
x 0 1 2
P(x) ) .15 .8 .05
So, expected value = (0)(0.15) +1(0.8)+2(0.05)
= 0 +0.8 +0.1
=0.9
Expected value =0.9
Now, let's find standard deviation
x

0
=0.1215
1
=0.008
2
=0.0605
Now, add the last column together and then take square root to find standard deviation.
Standard deviation of the distribution =
Simplify it, so standard deviation =0.4358898...
Round the answer to nearest four decimal places
Standard deviation = 0.4359
Look at the number and see if any of the number line goes over
Answer:
732
Step-by-step explanation:
Okay sub equation 2 into equation 1:
so it becomes
x + 3x = 8
4x = 8
x = 2
then 2 + y = 8, therefore y = 6
So the answer is B
Answer:
Step-by-step explanation:
This question is about the benefits of estimation.
1300/13 is easy and results in 100.
1287/13 can be approximated by 1300/13: 1287/13 ≈ 100.
Actually, 1287 = 1300 - 13 = 13(99); just subtract 1 from 100.
So: 1287/13 = 1300 - 13 = 1287. A nice bit of mental math!