Finding the Fourth Proportional to 9,882.74, 13,638.38 and 5,406.78

Step by Step Solution

1. Step 1: Write the proportion equation
   9,882.74 : 13,638.38 = 5,406.78 : x
2. Step 2: Convert to fraction form
   9,882.74/13,638.38 = 5,406.78/x
3. Step 3: Cross multiply
   9,882.74x = 13,638.38 × 5,406.78
4. Step 4: Simplify right side
   9,882.74x = 73,739,720.22
5. Step 5: Solve for x
   x = 73,739,720.22/9,882.74
6. Step 6: Final answer
   x = 7,461.47