Finding the Fourth Proportional to 10,426.65, 15,640.01 and 5,231.31

Step by Step Solution

1. Step 1: Write the proportion equation
   10,426.65 : 15,640.01 = 5,231.31 : x
2. Step 2: Convert to fraction form
   10,426.65/15,640.01 = 5,231.31/x
3. Step 3: Cross multiply
   10,426.65x = 15,640.01 × 5,231.31
4. Step 4: Simplify right side
   10,426.65x = 81,817,714.56
5. Step 5: Solve for x
   x = 81,817,714.56/10,426.65
6. Step 6: Final answer
   x = 7,846.98