Finding the Fourth Proportional to 9,290.90, 12,820.47 and 5,513.87

Step by Step Solution

1. Step 1: Write the proportion equation
   9,290.90 : 12,820.47 = 5,513.87 : x
2. Step 2: Convert to fraction form
   9,290.90/12,820.47 = 5,513.87/x
3. Step 3: Cross multiply
   9,290.90x = 12,820.47 × 5,513.87
4. Step 4: Simplify right side
   9,290.90x = 70,690,404.92
5. Step 5: Solve for x
   x = 70,690,404.92/9,290.90
6. Step 6: Final answer
   x = 7,608.56