Finding the Fourth Proportional to 21,828.18, 30,126.50 and 12,877.87

Step by Step Solution

1. Step 1: Write the proportion equation
   21,828.18 : 30,126.50 = 12,877.87 : x
2. Step 2: Convert to fraction form
   21,828.18/30,126.50 = 12,877.87/x
3. Step 3: Cross multiply
   21,828.18x = 30,126.50 × 12,877.87
4. Step 4: Simplify right side
   21,828.18x = 387,965,150.56
5. Step 5: Solve for x
   x = 387,965,150.56/21,828.18
6. Step 6: Final answer
   x = 17,773.59