Finding the Fourth Proportional to 8,391.87, 12,570.52 and 4,920.75

Step by Step Solution

1. Step 1: Write the proportion equation
   8,391.87 : 12,570.52 = 4,920.75 : x
2. Step 2: Convert to fraction form
   8,391.87/12,570.52 = 4,920.75/x
3. Step 3: Cross multiply
   8,391.87x = 12,570.52 × 4,920.75
4. Step 4: Simplify right side
   8,391.87x = 61,856,386.29
5. Step 5: Solve for x
   x = 61,856,386.29/8,391.87
6. Step 6: Final answer
   x = 7,370.99