Finding the Fourth Proportional to 9,360.78, 12,917.91 and 5,111.88

Step by Step Solution

1. Step 1: Write the proportion equation
   9,360.78 : 12,917.91 = 5,111.88 : x
2. Step 2: Convert to fraction form
   9,360.78/12,917.91 = 5,111.88/x
3. Step 3: Cross multiply
   9,360.78x = 12,917.91 × 5,111.88
4. Step 4: Simplify right side
   9,360.78x = 66,034,805.77
5. Step 5: Solve for x
   x = 66,034,805.77/9,360.78
6. Step 6: Final answer
   x = 7,054.41