Finding the Fourth Proportional to 10,499.81, 15,717.12 and 7,851.71

Step by Step Solution

1. Step 1: Write the proportion equation
   10,499.81 : 15,717.12 = 7,851.71 : x
2. Step 2: Convert to fraction form
   10,499.81/15,717.12 = 7,851.71/x
3. Step 3: Cross multiply
   10,499.81x = 15,717.12 × 7,851.71
4. Step 4: Simplify right side
   10,499.81x = 123,406,189.69
5. Step 5: Solve for x
   x = 123,406,189.69/10,499.81
6. Step 6: Final answer
   x = 11,753.19