Finding the Fourth Proportional to 21,142.46, 31,558.50 and 18,651.17

Step by Step Solution

1. Step 1: Write the proportion equation
   21,142.46 : 31,558.50 = 18,651.17 : x
2. Step 2: Convert to fraction form
   21,142.46/31,558.50 = 18,651.17/x
3. Step 3: Cross multiply
   21,142.46x = 31,558.50 × 18,651.17
4. Step 4: Simplify right side
   21,142.46x = 588,602,720.71
5. Step 5: Solve for x
   x = 588,602,720.71/21,142.46
6. Step 6: Final answer
   x = 27,839.85