Finding the Fourth Proportional to 21,359.18, 29,471.10 and 12,402.05

Step by Step Solution

1. Step 1: Write the proportion equation
   21,359.18 : 29,471.10 = 12,402.05 : x
2. Step 2: Convert to fraction form
   21,359.18/29,471.10 = 12,402.05/x
3. Step 3: Cross multiply
   21,359.18x = 29,471.10 × 12,402.05
4. Step 4: Simplify right side
   21,359.18x = 365,502,055.76
5. Step 5: Solve for x
   x = 365,502,055.76/21,359.18
6. Step 6: Final answer
   x = 17,112.18