Finding the Fourth Proportional to 6,985.82, 10,469.48 and 5,128.25

Step by Step Solution

1. Step 1: Write the proportion equation
   6,985.82 : 10,469.48 = 5,128.25 : x
2. Step 2: Convert to fraction form
   6,985.82/10,469.48 = 5,128.25/x
3. Step 3: Cross multiply
   6,985.82x = 10,469.48 × 5,128.25
4. Step 4: Simplify right side
   6,985.82x = 53,690,032.82
5. Step 5: Solve for x
   x = 53,690,032.82/6,985.82
6. Step 6: Final answer
   x = 7,685.57