Finding the Fourth Proportional to 9,616.76, 13,271.28 and 5,638.40

Step by Step Solution

1. Step 1: Write the proportion equation
   9,616.76 : 13,271.28 = 5,638.40 : x
2. Step 2: Convert to fraction form
   9,616.76/13,271.28 = 5,638.40/x
3. Step 3: Cross multiply
   9,616.76x = 13,271.28 × 5,638.40
4. Step 4: Simplify right side
   9,616.76x = 74,828,785.15
5. Step 5: Solve for x
   x = 74,828,785.15/9,616.76
6. Step 6: Final answer
   x = 7,781.08