Finding the Fourth Proportional to 9,142.15, 12,612.57 and 5,557.70

Step by Step Solution

1. Step 1: Write the proportion equation
   9,142.15 : 12,612.57 = 5,557.70 : x
2. Step 2: Convert to fraction form
   9,142.15/12,612.57 = 5,557.70/x
3. Step 3: Cross multiply
   9,142.15x = 12,612.57 × 5,557.70
4. Step 4: Simplify right side
   9,142.15x = 70,096,880.29
5. Step 5: Solve for x
   x = 70,096,880.29/9,142.15
6. Step 6: Final answer
   x = 7,667.44