Finding the Fourth Proportional to 9,521.91, 13,139.55 and 5,272.56

Step by Step Solution

1. Step 1: Write the proportion equation
   9,521.91 : 13,139.55 = 5,272.56 : x
2. Step 2: Convert to fraction form
   9,521.91/13,139.55 = 5,272.56/x
3. Step 3: Cross multiply
   9,521.91x = 13,139.55 × 5,272.56
4. Step 4: Simplify right side
   9,521.91x = 69,279,065.75
5. Step 5: Solve for x
   x = 69,279,065.75/9,521.91
6. Step 6: Final answer
   x = 7,275.75