Finding the Fourth Proportional to 9,120.34, 12,587.02 and 5,585.90

Step by Step Solution

1. Step 1: Write the proportion equation
   9,120.34 : 12,587.02 = 5,585.90 : x
2. Step 2: Convert to fraction form
   9,120.34/12,587.02 = 5,585.90/x
3. Step 3: Cross multiply
   9,120.34x = 12,587.02 × 5,585.90
4. Step 4: Simplify right side
   9,120.34x = 70,309,835.02
5. Step 5: Solve for x
   x = 70,309,835.02/9,120.34
6. Step 6: Final answer
   x = 7,709.12