Finding the Fourth Proportional to 2,147.88, 3,222.13 and 686.71

Step by Step Solution

1. Step 1: Write the proportion equation
   2,147.88 : 3,222.13 = 686.71 : x
2. Step 2: Convert to fraction form
   2,147.88/3,222.13 = 686.71/x
3. Step 3: Cross multiply
   2,147.88x = 3,222.13 × 686.71
4. Step 4: Simplify right side
   2,147.88x = 2,212,668.89
5. Step 5: Solve for x
   x = 2,212,668.89/2,147.88
6. Step 6: Final answer
   x = 1,030.16