Finding the Fourth Proportional to 9,865.80, 13,613.57 and 5,617.42

Step by Step Solution

1. Step 1: Write the proportion equation
   9,865.80 : 13,613.57 = 5,617.42 : x
2. Step 2: Convert to fraction form
   9,865.80/13,613.57 = 5,617.42/x
3. Step 3: Cross multiply
   9,865.80x = 13,613.57 × 5,617.42
4. Step 4: Simplify right side
   9,865.80x = 76,473,140.39
5. Step 5: Solve for x
   x = 76,473,140.39/9,865.80
6. Step 6: Final answer
   x = 7,751.34