Answer:
1) 120
2) E (Z) = 12 and Variance of Z = 90
a) 5 liters
Step-by-step explanation:
1. We can find this by suing combinations.
Here n= 10 and r= 3 so n C r
= 10 C 3= 120
2. E(X) = 8 and E(Y) = 3
Z = 2X - 3Y +5
E(Z ) = 2 E (X) - 3(E)(Y) +5 ( applying property for mean)
= 2(8) - 3(3)+ 5 = 16+5-9= 21-9= 12
V(X) = 9 and V(Y) = 6.
V(Z) = E(Z )²- V(X) *V(Y) (applying property for Variance for two variables )
= 144- 54= 90
3. 55 liters contain adulterated milk in 7: 4.
So it contains 4/ 11*55= 20 liters of water
But we want to make it a ratio of 7:6
the water will be 6/13 *55= 25.38 when rounded gives 25 liters of water
So 25- 20 = 5 liters must be added to make it a ratio of 7:6
Answer:
who is nathan
Step-by-step explanation:
do u know her
Answer:
StartFraction 7 over 2 EndFraction can be used to find the unit rate if one divides 7 by 2 and compares the result to 1
Step-by-step explanation:
we know that
The formula to calculate the slope between two points is equal to
we have the points
B(2, 7) and D(4, 14)
substitute the values
The unit rate is
therefore
StartFraction 7 over 2 EndFraction can be used to find the unit rate if one divides 7 by 2 and compares the result to 1
Answer:
Mr Smith gets a new job, every 5 months on the average.
Step-by-step explanation:
Mr Smith spends an average of 3 months on every job he gets.
Then he spends an average of 2 months in between jobs.
Meaning, on the average, if he has a job, he does it for 3 months, then leaves, lends the next 2 months without a job, then gets another job at the end of the 2 months without a job and then he repeats the cycle of 3 months on the job, 2 months without the job.
So, on the average it takes Mr. Smith, (3+2) months to get a new job.
