These days Sherri Floros spends her free time striding up stairs to her gym, trekking for hours along ski slopes, and imagining the thrill of standing 19,300 feet above sea level.

The Newton resident has only a few weeks before she takes on Mount Kilimanjaro, Africa’s highest peak and her toughest challenge. And the 47-year-old mother of two is determined to make it to the summit.