Why do fractions get smaller when you multiply it?

You have 138.72 in your saving account u take out 45.23 and 18.00 you deposit 75.85 into your account

9.4.34  question   to estimate the height of a stone  figure, an observer holds a small square up to her eyes and walks backward from the figure. she stops when the bottom of the figure aligns with the bottom edge of the  square, and when the top of the figure aligns with the top edge of the square. her eye level is 1.811.81 m from the ground. she is 3.703.70 m from the figure. what is the height of the figure to the nearest hundredth of a  meter?

What is the perimeter of an equilateral triangle if each side is (x+3)?