Answer:
a
The distribution of X is normal
b
c
Step-by-step explanation:
From the question we are told that
The population mean is 
The standard deviation is 
Generally given from the question that the amount of time spent alone by the population size is normally distributed then then the distribution of X (i.e the amount of time spent by the sample size (the one Mercurian)) will be normally distributed
Generally the probability that the child spend less than one hour in a day is mathematically represented as
Here 
So
From the z-table the value of
So
Generally the percentage of children that spends over 3.5 hours unsupervised is mathematically represented as
From the z-table the value of
So
Answer:
u=25.6
Step-by-step explanation:
6.4=u/4
by cross multiplication
6.4×4=u
25.6=u
i hope this will help you :)
Answer:
22. 18
23. 10
Step-by-step explanation:
22
- you plug the number for the variable into the equation (3(2)²+6
- order of operations say exponents first so you do 2²=4 so you have 3(4)+6
- then you multiple 3•4=12 so 12+6
- finally you add 12+6=18
23
- plug in the number for the variable so 5–(-5)
- so a negative and a minus will make it addition (negative + negative = positive)
- do it is 5+5 which equals 10
Answer:
x^4 + 2x^3 + 3x^2 + 2x + 2 = 0
Step-by-step explanation:
The computation of the polynomial equation of the lowest degree is shown below
As we know that the complex roots would always arise in the conjucate pairs
As -i is a root, i is also a root
As -1 + i is a root
And, -1 is also a root
Now the polynomial equation would be
(x + i)(x - i)(x + 1 - i)(x + 1 - i) = 0
(x^2 - i^2)[(x + 1)^2 - i^2] = 0
(x^2 + 1)[(x + 1)^2 + 1] = 0
(x^2 + 1)(x^2 + 2x + 2) = 0
x^4 + 2x^3 + 3x^2 + 2x + 2 = 0
When h=0, that is when it hits the ground
0=70-4t-16t²
based on your previous questions, you should have learned how to complete the square
solve by copmleting the square
minus 70 both sides
-70=-4t-16t²
times both sides by -1
70=4t+16t²
16t²+4t=70
divide both sides by 16
t²+1/4t=35/8
take 1/2 of the linear coefint and square it
half of 1/4=1/8, (1/8)²=1/64
add that to both sides
t²+1/4t+1/64=35/8+1/64
factor perfect square trionomial
square root both sides, remember to take positive and negative roots
minus 1/8
or
the 2nd solution is not valid because that gives us a negative time, before the ball was dropped
so
is the solution
t≈1.97
1.97 seconds
