Finding the Fourth Proportional to 9,985.28, 13,779.72 and 5,508.81

Step by Step Solution

1. Step 1: Write the proportion equation
   9,985.28 : 13,779.72 = 5,508.81 : x
2. Step 2: Convert to fraction form
   9,985.28/13,779.72 = 5,508.81/x
3. Step 3: Cross multiply
   9,985.28x = 13,779.72 × 5,508.81
4. Step 4: Simplify right side
   9,985.28x = 75,909,859.33
5. Step 5: Solve for x
   x = 75,909,859.33/9,985.28
6. Step 6: Final answer
   x = 7,602.18