x - 1st glass y - 2nd glass
x + y = 280 x = y + 80 y + 80 + y = 280 2 y = 200 y = 100 ml x = 100 + 80 x = 180 ml
The first glass contains 180 mL of water. We determined this by setting up an equation based on the relationships given in the problem. After solving, we found that the second glass holds 100 mL of water, leading to the first glass containing 180 mL.
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