Answer:w= 25
Explanation:
Cost of bottle of water = (w-1)cents
Cost of bottle of milk = (2w-11)cents
Let x bottles of water cost $4.80= 480 cents
Also,x bottles of milk cost $7.80= 780 cents
x(w-1)= 480
x(2w-11) = 780
x = 480/w-1 = 780/2w-11
960w -5280= 780w-780
180w = 4500
w= 25