Finding the Fourth Proportional to 9,621.54, 13,277.78 and 5,642.72

Step by Step Solution

1. Step 1: Write the proportion equation
   9,621.54 : 13,277.78 = 5,642.72 : x
2. Step 2: Convert to fraction form
   9,621.54/13,277.78 = 5,642.72/x
3. Step 3: Cross multiply
   9,621.54x = 13,277.78 × 5,642.72
4. Step 4: Simplify right side
   9,621.54x = 74,922,794.76
5. Step 5: Solve for x
   x = 74,922,794.76/9,621.54
6. Step 6: Final answer
   x = 7,786.99