Explanation:
Regardless of the number of factors, the product will be negative if an odd number of factors are negative.
In the example, 3 of the factors are negative. 3 is an odd number so the product will be negative.
-2*-3*-1*1 = -6
_____
Of course, the product will be zero if any factor is zero, regardless of the signs of any other factors.
At the bank, Derek made 7 withdrawals, each in the same amount. His brother, John, made 5 withdrawls, each in the same amount.
Let x be the amount of one of Derek's withdrawals
Each of John's withdrawals was $5 more than each withdrawal that Derek made.
x + 5 is t the amount of one of John's withdrawals
Derek made 7 withdrawals
So amount withdraw 7 times = 7x
John made 5 withdrawals
So amount withdraw 5 times = 5(x+5)
Both Derek and John withdrew the same amount of money in the end
(A) 7x = 5(x+5)
(B) Solve for x
7x = 5x + 25
Subtract 5x from both sides
2x = 25
Divide by 2
x = 12.5
(C) check your solution
we plug in 12.5 for x in 7x= 5x + 25
7(12.5) = 5(12.5) + 25
87.5 = 62.5+ 25
87.5 = 87.5
(D) Each brother withdrawal 87.5 dollars
Answer:
E(w) = 1600000
v(w) = 240000
Step-by-step explanation:
given data
sequence = 1 million iid (+1 and +2)
probability of transmitting a +1 = 0.4
solution
sequence will be here as
P{Xi = k } = 0.4 for k = +1
0.6 for k = +2
and define is
x1 + x2 + ................ + X1000000
so for expected value for W
E(w) = E( x1 + x2 + ................ + X1000000 ) ......................1
as per the linear probability of expectation
E(w) = 1000000 ( 0.4 × 1 + 0.6 × 2)
E(w) = 1600000
and
for variance of W
v(w) = V ( x1 + x2 + ................ + X1000000 ) ..........................2
v(w) = V x1 + V x2 + ................ + V X1000000
here also same as that xi are i.e d so cov(xi, xj ) = 0 and i ≠ j
so
v(w) = 1000000 ( v(x) )
v(w) = 1000000 ( 0.24)
v(w) = 240000
36 3/4 = 36.75
36 3/8 = 36.375
37 1/2 = 37.5
36 5/8 = 36.625
(36.75 + 36.375 + 37.5 + z) / 4 = 36.625
(110.625 + z) / 4 = 36.625
110.625 + z = 36.625 * 4
110.625 + z = 146.5
z = 146.5 - 110.625
z = 35.875 or 35 7/8 <===
8, 2 because A doesn't add anything.