Finding the Fourth Proportional to 9,161.71, 12,642.38 and 5,578.27

Step by Step Solution

1. Step 1: Write the proportion equation
   9,161.71 : 12,642.38 = 5,578.27 : x
2. Step 2: Convert to fraction form
   9,161.71/12,642.38 = 5,578.27/x
3. Step 3: Cross multiply
   9,161.71x = 12,642.38 × 5,578.27
4. Step 4: Simplify right side
   9,161.71x = 70,522,570.50
5. Step 5: Solve for x
   x = 70,522,570.50/9,161.71
6. Step 6: Final answer
   x = 7,697.54