Finding the Fourth Proportional to 21,602.50, 29,812 and 13,105.06

Step by Step Solution

1. Step 1: Write the proportion equation
   21,602.50 : 29,812 = 13,105.06 : x
2. Step 2: Convert to fraction form
   21,602.50/29,812 = 13,105.06/x
3. Step 3: Cross multiply
   21,602.50x = 29,812 × 13,105.06
4. Step 4: Simplify right side
   21,602.50x = 390,688,048.72
5. Step 5: Solve for x
   x = 390,688,048.72/21,602.50
6. Step 6: Final answer
   x = 18,085.32