Question

your friend drinks 2/3 of a bottle of water. You drink 5/7 of a bottle of water. FInd the difference of the amounts of water left in each bottle?

Answer 1

amount left in friends bottle = 1 - 2/3 = 1/3
amount left in your bottle = 1 - 5/7  = 2/7

Difference = 1/3 - 2/7  = 7/21 - 6/21  = 1/21 Answer

Answer 2

Answer:

The difference of the amounts of water left in each bottle is 1/21 of the bottle.

Step-by-step explanation:

Your friend drinks 2/3 of the bottle, which is a bottle divide in 3 parts and remove o take 2 parts, only rest 1 parts of the 3, that is the same to say tata remain 1/3 of the bottle of water. That also can be proved with the following calculation:

$1 - \frac{2}{3}= \frac{1}{1} - \frac{2}{3} = \frac{(1*3) - (1*2)}{1*3} = \frac{3-2}{3} = \frac{1}{3}$

Your friend drinks 5/7 of the bottle, which is a bottle divide in 7 parts and remove o take 5 parts, only rest 2 parts of the 7, that is the same to say tata remain 2/7 of the bottle of water. That also can be proved with the following calculation:

$1 - \frac{5}{7}= \frac{1}{1}- \frac{5}{7} = \frac{(1*7) - (1*5)}{1*7} = \frac{7-5}{7} = \frac{2}{7}$

Finally we have to find the difference between the two remains of the bottle, that can be made by a simple subtraction:

$\frac{1}{3}- \frac{2}{7} = \frac{(1*7) - (3*2)}{3*7} = \frac{7-6}{21} = \frac{1}{21}$

Then, the difference of the amounts of water left in each bottle is 1/21 of the bottle.