Finding the Third Proportional to 858,289 and 1,298,478

Step by Step Solution

1. Step 1: Write the proportion equation
   858,289 : 1,298,478 = 1,298,478 : x
2. Step 2: Convert to fraction form
   858,289/1,298,478 = 1,298,478/x
3. Step 3: Cross multiply
   858,289x = 1,298,478 × 1,298,478
4. Step 4: Simplify right side
   858,289x = 1,686,045,116,484
5. Step 5: Solve for x
   x = 1,686,045,116,484/858,289
6. Step 6: Final answer
   x = 1,964,425.87