Finding the Fourth Proportional to 2,072.13, 3,107.39 and 772.89

Step by Step Solution

1. Step 1: Write the proportion equation
   2,072.13 : 3,107.39 = 772.89 : x
2. Step 2: Convert to fraction form
   2,072.13/3,107.39 = 772.89/x
3. Step 3: Cross multiply
   2,072.13x = 3,107.39 × 772.89
4. Step 4: Simplify right side
   2,072.13x = 2,401,666.79
5. Step 5: Solve for x
   x = 2,401,666.79/2,072.13
6. Step 6: Final answer
   x = 1,159.03