Finding the Fourth Proportional to 9,778.56, 14,648.40 and 5,385.12

Step by Step Solution

1. Step 1: Write the proportion equation
   9,778.56 : 14,648.40 = 5,385.12 : x
2. Step 2: Convert to fraction form
   9,778.56/14,648.40 = 5,385.12/x
3. Step 3: Cross multiply
   9,778.56x = 14,648.40 × 5,385.12
4. Step 4: Simplify right side
   9,778.56x = 78,883,391.81
5. Step 5: Solve for x
   x = 78,883,391.81/9,778.56
6. Step 6: Final answer
   x = 8,066.97