Finding the Fourth Proportional to 105,429.26, 145,478.01 and 62,978.78

Step by Step Solution

1. Step 1: Write the proportion equation
   105,429.26 : 145,478.01 = 62,978.78 : x
2. Step 2: Convert to fraction form
   105,429.26/145,478.01 = 62,978.78/x
3. Step 3: Cross multiply
   105,429.26x = 145,478.01 × 62,978.78
4. Step 4: Simplify right side
   105,429.26x = 9,162,027,586.63
5. Step 5: Solve for x
   x = 9,162,027,586.63/105,429.26
6. Step 6: Final answer
   x = 86,902.13