Finding the Fourth Proportional to 21,200.28, 29,256.50 and 13,247.12

Step by Step Solution

1. Step 1: Write the proportion equation
   21,200.28 : 29,256.50 = 13,247.12 : x
2. Step 2: Convert to fraction form
   21,200.28/29,256.50 = 13,247.12/x
3. Step 3: Cross multiply
   21,200.28x = 29,256.50 × 13,247.12
4. Step 4: Simplify right side
   21,200.28x = 387,564,153.76
5. Step 5: Solve for x
   x = 387,564,153.76/21,200.28
6. Step 6: Final answer
   x = 18,281.09