Finding the Fourth Proportional to 105.90, 145.83 and 73.09

Step by Step Solution

1. Step 1: Write the proportion equation
   105.90 : 145.83 = 73.09 : x
2. Step 2: Convert to fraction form
   105.90/145.83 = 73.09/x
3. Step 3: Cross multiply
   105.90x = 145.83 × 73.09
4. Step 4: Simplify right side
   105.90x = 10,658.71
5. Step 5: Solve for x
   x = 10,658.71/105.90
6. Step 6: Final answer
   x = 100.65