Answer:Mark Is 9 years old; Christine is 5 years old
Step-by-step explanation:
Present age
LET mark age be x
Christine be x-4 yrs
In 3 yrs Time
Mark will be x+3 yrs old
Christine will be (x -4 +3) = x-1 years old
Also, In 3 years time
Christine = 2/3 Mark
such that
x-1 = 2/3(x+3)
x -1= 2x+6 / 3
3x -3= 2x+6
3X--2X = 6+3
=X=9
Mark Is 9 years old
Christine is x -4 = 9-4=5 years old
Answer:
The more money you invest and the earlier you start means your retirement savings will have that much more time and potential to grow and investing early you can be able to take advantage of compound earnings.
Step-by-step explanation:
Answer:
Work out the area of this circle. Take pie to be 3.142 and give your answer to 2 decimal places.
Step-by-step explanation:
Answer:
![P(X \geq 7) = P(X=7) +P(X=8)](https://tex.z-dn.net/?f=%20P%28X%20%5Cgeq%207%29%20%3D%20P%28X%3D7%29%20%2BP%28X%3D8%29)
And we can find the individual probabilities using the probability mass function
And replacing we got:
![P(X \geq 7) = P(X=7) +P(X=8)=0.3826 +0.4305=0.8131](https://tex.z-dn.net/?f=%20P%28X%20%5Cgeq%207%29%20%3D%20P%28X%3D7%29%20%2BP%28X%3D8%29%3D0.3826%20%2B0.4305%3D0.8131)
Step-by-step explanation:
Previous concepts
The binomial distribution is a "DISCRETE probability distribution that summarizes the probability that a value will take one of two independent values under a given set of parameters. The assumptions for the binomial distribution are that there is only one outcome for each trial, each trial has the same probability of success, and each trial is mutually exclusive, or independent of each other".
Solution to the problem
Let X the random variable of interest "number of automobiles with both headligths working", on this case we now that:
The probability mass function for the Binomial distribution is given as:
Where (nCx) means combinatory and it's given by this formula:
And for this case we want to find this probability:
![P(X \geq 7) = P(X=7) +P(X=8)](https://tex.z-dn.net/?f=%20P%28X%20%5Cgeq%207%29%20%3D%20P%28X%3D7%29%20%2BP%28X%3D8%29)
And we can find the individual probabilities using the probability mass function
And replacing we got:
![P(X \geq 7) = P(X=7) +P(X=8)=0.3826 +0.4305=0.8131](https://tex.z-dn.net/?f=%20P%28X%20%5Cgeq%207%29%20%3D%20P%28X%3D7%29%20%2BP%28X%3D8%29%3D0.3826%20%2B0.4305%3D0.8131)
I'm sorry that it's past 11pm, but if it still helps, the answer is 204/-576 which simplifies to 51/-144