You can
put this solution on YOUR website!I will do question only.
(2) Erin's age is 3 times Warren's. In 4 years she will be twice as old as he will be. How old is each now.
I will do question (2) first.
Warren's age now is x.
Erin's age now is 3x.
In 4 years, they both will be 4 years older, right?
3x + 4 = Erin's age 4 years form now.
x + 4 = Warren's age 4 years from now.
3x + 4 = 2(x + 4)
3x + 4 = 2x + 8
3x - 2x = 8 - 4
x = 4
Warren is 4 years old now.
Erin is 3(4) years old now or 12 years old.
Did you follow?
For question (1), you are dealing with two equations in two variables.
You can
put this solution on YOUR website!so the speed of the sailboat downstream is

the speed of the sailboat upstream is
the speed of the stream is
speed of sailboat in still water is