Finding the Fourth Proportional to 9,899.72, 13,661.95 and 5,423.86

Step by Step Solution

1. Step 1: Write the proportion equation
   9,899.72 : 13,661.95 = 5,423.86 : x
2. Step 2: Convert to fraction form
   9,899.72/13,661.95 = 5,423.86/x
3. Step 3: Cross multiply
   9,899.72x = 13,661.95 × 5,423.86
4. Step 4: Simplify right side
   9,899.72x = 74,100,435.82
5. Step 5: Solve for x
   x = 74,100,435.82/9,899.72
6. Step 6: Final answer
   x = 7,485.11