Finding the Fourth Proportional to 21,192.18, 29,238.45 and 12,238.50

Step by Step Solution

1. Step 1: Write the proportion equation
   21,192.18 : 29,238.45 = 12,238.50 : x
2. Step 2: Convert to fraction form
   21,192.18/29,238.45 = 12,238.50/x
3. Step 3: Cross multiply
   21,192.18x = 29,238.45 × 12,238.50
4. Step 4: Simplify right side
   21,192.18x = 357,834,770.33
5. Step 5: Solve for x
   x = 357,834,770.33/21,192.18
6. Step 6: Final answer
   x = 16,885.23