In a given year, 94 cities in the world had populations of 1 million or more. Fifty years later, 530 cities had populations of 1 million or more. What was the percent increase?

The percent increase was of 464%.

Step-by-step explanation:

To find the percent increase, first we find how much the current amount is of the original amount. Then, we subtract the current amount from the original amount.

Percentage of current amount:

We solve this using a rule of three.

The original amount(94 cities), was 100% = 1.

The current amount(530 cities) is x. So

94 cities - 1

530 cities - x

94x = 530

x = 530/94

x = 5.64

5.64 = 564% of the original amount

What was the percent increase?

The current amount is 564%

The original amount is 100%

564 - 100 = 464

The percent increase was of 464%.

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