Answer:
0.8 euro
Step-by-step explanation:
Suppose the price of bottle of lemonade is x, when the bottle of water costs y.
Four bottles of lemonade cost 4x, two bottles of water cost 2y
4x+2y=2.45
Two bottles of lemonade cost 2x, four bottles of water cost 4y
2x+4y= 2.35
These equations( 4x+2y=2.45 and 2x+4y= 2.35) are simultaneous, so
multiply the first one by -2
-8x-4y=-4.9
-8x-4y+2x+4y= -4.9+2.35
-6x=-2.55
x=0.425 euro - the cost of bottle of lemonade
y=(2.45-4*0.425)/2
y=0.375 euro - the cost of bottle of water
0.425+0.375= 0.8 euro - the total cost of one bottle of
lemonade and one bottle of water
