Answer:
12/7 hours
Step-by-step explanation:
First find the rate for hour for the two. For Lianne she can do 1/3 of the job per hour. For Julie she can do 1/4 of the job per hour.
Adding them together, 1/3+1/4= 7/12.
This 7/12 means that working together they can finish 7/12 of a job in an hour. We can use the speed*time=distance formula here and see that
7/12 * time = 1 job done
time = 12/7 hours.
Yep! Good job, you did it correctly.
Your y-intercept is equal to the constant of the equation (y-int = -2). Your movement/direction (or rise over run) is equal to the variable. Since your variable is x (which can also be written as 1x) means you move up one and over one (rise over run). This is because 1/1 is equal to 1.
Answer:
(a) E(X) = -2p² + 2p + 2; d²/dp² E(X) at p = 1/2 is less than 0
(b) 6p⁴ - 12p³ + 3p² + 3p + 3; d²/dp² E(X) at p = 1/2 is less than 0
Step-by-step explanation:
(a) when i = 2, the expected number of played games will be:
E(X) = 2[p² + (1-p)²] + 3[2p² (1-p) + 2p(1-p)²] = 2[p²+1-2p+p²] + 3[2p²-2p³+2p(1-2p+p²)] = 2[2p²-2p+1] + 3[2p² - 2p³+2p-4p²+2p³] = 4p²-4p+2-6p²+6p = -2p²+2p+2.
If p = 1/2, then:
d²/dp² E(X) = d/dp (-4p + 2) = -4 which is less than 0. Therefore, the E(X) is maximized.
(b) when i = 3;
E(X) = 3[p³ + (1-p)³] + 4[3p³(1-p) + 3p(1-p)³] + 5[6p³(1-p)² + 6p²(1-p)³]
Simplification and rearrangement lead to:
E(X) = 6p⁴-12p³+3p²+3p+3
if p = 1/2, then:
d²/dp² E(X) at p = 1/2 = d/dp (24p³-36p²+6p+3) = 72p²-72p+6 = 72(1/2)² - 72(1/2) +6 = 18 - 36 +8 = -10
Therefore, E(X) is maximized.
Answer:
Is a consistent independent system
Step-by-step explanation:
we have
-----> isolate the variable y
----> equation A
-----> isolate the variable y
---> equation B
Compare equation A and equation B
We can affirm that
The slopes are not equal ( so the lines are not parallel)
The lines are different
The product of their slopes is equal to -1 (the lines are perpendicular)
so
The system of equations has only one solution
therefore
Is a consistent independent system
