Finding the Fourth Proportional to 12,977.78, 17,910.74 and 7,945.39

Step by Step Solution

1. Step 1: Write the proportion equation
   12,977.78 : 17,910.74 = 7,945.39 : x
2. Step 2: Convert to fraction form
   12,977.78/17,910.74 = 7,945.39/x
3. Step 3: Cross multiply
   12,977.78x = 17,910.74 × 7,945.39
4. Step 4: Simplify right side
   12,977.78x = 142,307,789.58
5. Step 5: Solve for x
   x = 142,307,789.58/12,977.78
6. Step 6: Final answer
   x = 10,965.49