Acircular region has a population of about 15,500 people and a population density of about 775 people per square kilometer. find the radius of the region. round your answer to the nearest tenth.
i got 1.4, but it's wrong. anyone know the rough steps to this problem?

What is the equation in point slope form of the line that passes through the point (-1, -3) and has a slope of 4? y-1=4(x-3) or y+3=4(x+1)

You have a 32-foot fence around a square garden. there are 4 equal sections. you paint 13 of one section of the fence. what fraction of the fence did you paint? you have a 32-foot fence around a square garden. there are 4 equal sections. you paint 13 of one section of the fence. what fraction of the fence did you paint?

Becca wants to mix fruit juice and soda to make a punch. she can buy fruit juice for $3 a gallon and soda for $4 a gallon. if she wants to make 28 gallons of punch at a cost of $3.25 a gallon, how many gallons of fruit juice and how many gallons of soda should she buy?