Finding the Fourth Proportional to 105.77, 145.83 and 86.03

Step by Step Solution

1. Step 1: Write the proportion equation
   105.77 : 145.83 = 86.03 : x
2. Step 2: Convert to fraction form
   105.77/145.83 = 86.03/x
3. Step 3: Cross multiply
   105.77x = 145.83 × 86.03
4. Step 4: Simplify right side
   105.77x = 12,545.90
5. Step 5: Solve for x
   x = 12,545.90/105.77
6. Step 6: Final answer
   x = 118.61