Finding the Fourth Proportional to 11,100.50, 16,639.12 and 5,172.50

Step by Step Solution

1. Step 1: Write the proportion equation
   11,100.50 : 16,639.12 = 5,172.50 : x
2. Step 2: Convert to fraction form
   11,100.50/16,639.12 = 5,172.50/x
3. Step 3: Cross multiply
   11,100.50x = 16,639.12 × 5,172.50
4. Step 4: Simplify right side
   11,100.50x = 86,065,773.57
5. Step 5: Solve for x
   x = 86,065,773.57/11,100.50
6. Step 6: Final answer
   x = 7,753.32