Finding the Fourth Proportional to 8,667.62, 11,957.46 and 5,128.79

Step by Step Solution

1. Step 1: Write the proportion equation
   8,667.62 : 11,957.46 = 5,128.79 : x
2. Step 2: Convert to fraction form
   8,667.62/11,957.46 = 5,128.79/x
3. Step 3: Cross multiply
   8,667.62x = 11,957.46 × 5,128.79
4. Step 4: Simplify right side
   8,667.62x = 61,327,241.49
5. Step 5: Solve for x
   x = 61,327,241.49/8,667.62
6. Step 6: Final answer
   x = 7,075.44