There are 9 girls and 11 boys in a class at a Private School. Of these students, 3 girls and 4 boys are in
the Running Club. What percentage of the students
at this Private School are in the Running Club?%

i needdd help pl

35%

Step-by-step explanation:

9+11=20

3+4=7

20*5=100

7*5=35

answer: .64

step-by-step explanation

set up the formula for standard deviation for this set of numbers, then simplify

let's call the solutions x₁ = (5 - 2√7)/3 and x₂ = (5 + 2√7)/3

then the equation is (x-x₁)(x-x₂) = 0

if you fill that in you get a lot of numbers which you can recognize as ax²+bx+c=0.

step-by-step explanation:

you can see that a=1 (there is just an x²)

b = (-5 -2√7 + 2√7 - 5)/3 = -10/3

c = -2√7)/3 ) * (-5+2√7)/3) = -1/3

so your answer is 3x^2 – 10x – 1 = 0