On average, we sleep one-third of our life. (2) Usually, the amount that we sleep decreases with age. (3) As newborns, we sleep up to 20 hours a day. (4) At age 4 or so, we sleep about 12 hours. (5) By the time we’re 10, we sleep about 10 hours. (6) _____, as adults, we sleep 7-9 hours. (7) Eventually, when we’re elderly, we may sleep only 4-6 hours.