This is a system of equations problem.
Blueberry = X, blackberry = Y
Joe:
5x + 10y = 135
James:
x + 9y = 104
Let’s isolate x from James’ equation.
x = 104 - 9y
Now substitute that into the first equation.
5(104 - 9y) + 10y = 135
520 - 45y + 10y = 135
-35y = -385
y = -385/-35. The negatives cancel out, leaving us with $11 for blackberries.
Now we can substitute that value into James’s equation.
x + 9(11) = 104
x = 104 - 99
x = $5
Final answer: Blueberry pies cost $5, blackberry pies cost $11.
They live 9 3/4 blocks away from eachother
Remember: 50% means 1/2. So, if 18 is 50%, or 1/2, of a number, the number must be double 18.
18 x 2 = 36
18 is 50% of 36.
It would be 14 for the perimeter