Finding the Fourth Proportional to 105,312.54, 145,384.83 and 71,499.90

Step by Step Solution

1. Step 1: Write the proportion equation
   105,312.54 : 145,384.83 = 71,499.90 : x
2. Step 2: Convert to fraction form
   105,312.54/145,384.83 = 71,499.90/x
3. Step 3: Cross multiply
   105,312.54x = 145,384.83 × 71,499.90
4. Step 4: Simplify right side
   105,312.54x = 10,395,000,806.52
5. Step 5: Solve for x
   x = 10,395,000,806.52/105,312.54
6. Step 6: Final answer
   x = 98,706.20