Finding the Fourth Proportional to 9,898.55, 13,660.04 and 5,422.20

Step by Step Solution

1. Step 1: Write the proportion equation
   9,898.55 : 13,660.04 = 5,422.20 : x
2. Step 2: Convert to fraction form
   9,898.55/13,660.04 = 5,422.20/x
3. Step 3: Cross multiply
   9,898.55x = 13,660.04 × 5,422.20
4. Step 4: Simplify right side
   9,898.55x = 74,067,441.78
5. Step 5: Solve for x
   x = 74,067,441.78/9,898.55
6. Step 6: Final answer
   x = 7,482.66