Finding the Fourth Proportional to 105,890.42, 146,128.78 and 58,143.77

Step by Step Solution

1. Step 1: Write the proportion equation
   105,890.42 : 146,128.78 = 58,143.77 : x
2. Step 2: Convert to fraction form
   105,890.42/146,128.78 = 58,143.77/x
3. Step 3: Cross multiply
   105,890.42x = 146,128.78 × 58,143.77
4. Step 4: Simplify right side
   105,890.42x = 8,496,478,174.70
5. Step 5: Solve for x
   x = 8,496,478,174.70/105,890.42
6. Step 6: Final answer
   x = 80,238.40