You have a 3 and a 5 liter water container, each container has no markings except for that which gives you it's total volume. You also have a running tap. You must use the containers and the tap in such away as to exactly measure out 4 liters of water. How is this done?
Option 1:
a. Fill 5 liter bottle from tap first
b. Empty 5 liter bottle into 3 liter bottle - leaving 2 liters in 5 liter can.
c. Pour away the water of 3 liter bottle.
d. Pour 2 liters of water from 5 liter bottle to 3 liter bottle - leaving 2 liters in 3 liter bottle and 5 liter bottle as empty.
e. Now fill 5 liter from tap and then fill the 3 liter bottle from 5 liter bottle, which makes 3 liters in 3 liter can and 4 liters of water in 5 liter bottle.
Option 2:
a. Fill 3 liter bottle from tap.
b. Empty this 3 liter bottle in 5 liter bottle - leaving 3 liters in 5 liter bottle and 3 liter can empty.
c. again fill 3 liter bottle from tap and fill 5 liter bottle from 3 liter bottle - leaving 5 liter bottle full and 1 liter in 3 liter bottle.
d. Now pour away 5 liter bottle and fill 1 liter water from 3 liter bottle to 5 liter bottle - leaving 1 liter in 5 liter bottle and 3 liter bottle as empty
e. Fill 3 liter bottle from tap and empty it in 5 liter bottle - leaving 4 liters in 5 liter bottle.
Option 1:
a. Fill 5 liter bottle from tap first
b. Empty 5 liter bottle into 3 liter bottle - leaving 2 liters in 5 liter can.
c. Pour away the water of 3 liter bottle.
d. Pour 2 liters of water from 5 liter bottle to 3 liter bottle - leaving 2 liters in 3 liter bottle and 5 liter bottle as empty.
e. Now fill 5 liter from tap and then fill the 3 liter bottle from 5 liter bottle, which makes 3 liters in 3 liter can and 4 liters of water in 5 liter bottle.
Option 2:
a. Fill 3 liter bottle from tap.
b. Empty this 3 liter bottle in 5 liter bottle - leaving 3 liters in 5 liter bottle and 3 liter can empty.
c. again fill 3 liter bottle from tap and fill 5 liter bottle from 3 liter bottle - leaving 5 liter bottle full and 1 liter in 3 liter bottle.
d. Now pour away 5 liter bottle and fill 1 liter water from 3 liter bottle to 5 liter bottle - leaving 1 liter in 5 liter bottle and 3 liter bottle as empty
e. Fill 3 liter bottle from tap and empty it in 5 liter bottle - leaving 4 liters in 5 liter bottle.