Finding the Fourth Proportional to 9,521.28, 13,139.51 and 5,485.88

Step by Step Solution

1. Step 1: Write the proportion equation
   9,521.28 : 13,139.51 = 5,485.88 : x
2. Step 2: Convert to fraction form
   9,521.28/13,139.51 = 5,485.88/x
3. Step 3: Cross multiply
   9,521.28x = 13,139.51 × 5,485.88
4. Step 4: Simplify right side
   9,521.28x = 72,081,780.54
5. Step 5: Solve for x
   x = 72,081,780.54/9,521.28
6. Step 6: Final answer
   x = 7,570.60