Finding the Third Proportional to 1,138.78 and 1,711.69

Step by Step Solution

1. Step 1: Write the proportion equation
   1,138.78 : 1,711.69 = 1,711.69 : x
2. Step 2: Convert to fraction form
   1,138.78/1,711.69 = 1,711.69/x
3. Step 3: Cross multiply
   1,138.78x = 1,711.69 × 1,711.69
4. Step 4: Simplify right side
   1,138.78x = 2,929,874.10
5. Step 5: Solve for x
   x = 2,929,874.10/1,138.78
6. Step 6: Final answer
   x = 2,572.82