Acity has the population of 350,000 persons the population has decreased by 30% in the past 10 years what is the population of the city 10 years ago

As per the statement: A city has the population of 350,000 persons the population has decreased by 30% in the past 10 years.

The formula for calculating the percent change between two values over the time is given by:

where

p represents the percent change

A represents the New value

B represents the Old value

Since, p is the percent(decreased) = -30

Substitute the given values and solve for B;

then;

Divide both sides by 100 we get;

By cross multiply we get;

Add both sides B we get;

Divide both sides by 0.7 we get;

B = 500,000

Therefore, the population of city 10 years ago before 305 decrease in population was 500,000