Finding the Fourth Proportional to 9,120.57, 12,587.57 and 5,142.93

Step by Step Solution

1. Step 1: Write the proportion equation
   9,120.57 : 12,587.57 = 5,142.93 : x
2. Step 2: Convert to fraction form
   9,120.57/12,587.57 = 5,142.93/x
3. Step 3: Cross multiply
   9,120.57x = 12,587.57 × 5,142.93
4. Step 4: Simplify right side
   9,120.57x = 64,736,991.38
5. Step 5: Solve for x
   x = 64,736,991.38/9,120.57
6. Step 6: Final answer
   x = 7,097.91