Finding the Fourth Proportional to 21,779.78, 32,628.56 and 12,868.52

Step by Step Solution

1. Step 1: Write the proportion equation
   21,779.78 : 32,628.56 = 12,868.52 : x
2. Step 2: Convert to fraction form
   21,779.78/32,628.56 = 12,868.52/x
3. Step 3: Cross multiply
   21,779.78x = 32,628.56 × 12,868.52
4. Step 4: Simplify right side
   21,779.78x = 419,881,049.45
5. Step 5: Solve for x
   x = 419,881,049.45/21,779.78
6. Step 6: Final answer
   x = 19,278.48