Finding the Fourth Proportional to 9,907.91, 13,672.55 and 5,928.78

Step by Step Solution

1. Step 1: Write the proportion equation
   9,907.91 : 13,672.55 = 5,928.78 : x
2. Step 2: Convert to fraction form
   9,907.91/13,672.55 = 5,928.78/x
3. Step 3: Cross multiply
   9,907.91x = 13,672.55 × 5,928.78
4. Step 4: Simplify right side
   9,907.91x = 81,061,511.35
5. Step 5: Solve for x
   x = 81,061,511.35/9,907.91
6. Step 6: Final answer
   x = 8,181.50