Finding the Fourth Proportional to 9,866.42, 13,615.42 and 5,390.18

Step by Step Solution

1. Step 1: Write the proportion equation
   9,866.42 : 13,615.42 = 5,390.18 : x
2. Step 2: Convert to fraction form
   9,866.42/13,615.42 = 5,390.18/x
3. Step 3: Cross multiply
   9,866.42x = 13,615.42 × 5,390.18
4. Step 4: Simplify right side
   9,866.42x = 73,389,537.62
5. Step 5: Solve for x
   x = 73,389,537.62/9,866.42
6. Step 6: Final answer
   x = 7,438.32