Answer:
0
Step-by-step explanation:
2a+ 2/a =4
Multiply each side by a to clear the fraction
a( 2a+ 2/a) =4*a
Distribute
2a^2 +2 = 4a
Subtract 4a from each side
2a^2 -4a +2 = 4a-4a
2a^2 -4a +2 =0
Divide by 2
2/2 a^2 -4a/2 +2/2 =0/2
a^2 -2a +1=0
Factor
(a-1) (a-1) =0
Using the zero product property
a=1
2a^2 -2/a^2
2(1)^2 -2/1^2
2-2
0
Answer:
Approximate probability that the number of households that use the Internet for banking in a sample of 1000 is less than or equal to 130 is less than 0.0005% .
Step-by-step explanation:
We are given that let X be the number that do some or all of their banking on the Internet.
Also; Mean, 
= 310/1000 or 0.31 and Standard deviation, 
= 14.63/1000 = 0.01463 .
We know that Z = 
~ N(0,1)
Probability that the number of households that use the Internet for banking in a sample of 1000 is less than or equal to 130 is given by P(X <= 130/1000);
P(X <=0.13) = P( <= 
) = P(Z <= -12.303) = P(Z > 12.303)
Since this value is not represented in the z table as the value is very high and z table is limited to x = 4.4172.
So, after seeing the table we can say that this probability is approximately less than 0.0005% .
So x + y = 45, and 4x + 5y = 195. Get y by itself. Subtract x from both sides in the first equation to get y = 45 -x, and subtract 4x from the second equation to get 5y = 195 - 4x. Divide by 5 to both sides to get y = 39 - 4/5x. 39 - 4/5x = 45 - x. Add x to both sides to get 39 - 1/5x = 45. Subtract 39 from both sides to get -1/5x = 6. Divide by -1/5 to get x = -30, or 30. In the first equation, do 30 + y = 45. Subtract 30 from both sides to get y = 15. Check. 4(30) + 15(5) = 195, or 120 + 75 = 195.
What numbers? I need to know that to answer :/
