Answer:
approx 193200
Step-by-step explanation:
As known for normal distribution is correct the rule 95.4% of the results are situation within mean+-2*s ( where s is a standard deviation)
So the border is 100+-2*15=70 and that is approx=67.
95.4% of 84000000 citizens are= 8 400 000*0.954=8013600 persons
So the residual number of the citizens =8400000-8013600=386400 citizens
Because of the simmetry of normal distribution to find the number of the citizens that have IQ below 67 we have to divide 386400 by 2.
N=386000/2=193200
Answer:
So, Width = 7/2 or 3.5
Length = 4
Step-by-step explanation:
Area of rectangle = 14 ft^2
Let width of rectangle 2 = x
and Length of rectangle = 2x-3
Formula used for area of rectangle
Area = Length * Width
14 = (2x - 3) x
14 = 2x^2 - 3x
=> 2x^2 -3x -14 = 0
Solving the quadratic equation using factorization
-28 x^2 = -7x * -4x
2x^2 -7x + 4x -14 = 0
x (2x -7) +2(2x-7) = 0
(x+2) (2x-7) =0
=> x + 2 =0 and 2x -7 = 0
x = -2 and x = 7/2
Since width cannot be negative so, x= 7/2
Width= x = 7/2
Length = 2x -3 => 2(7/2) - 3
=> 7 -3
=> 4
So, Width = 7/2 or 3.5
Length = 4.
Answer:
one solution and x=40
Step-by-step explanation:
8x-32=6x+48
2x=80
80÷2
x=40