Finding the Third Proportional to 289,686 and 424,158.75

Step by Step Solution

1. Step 1: Write the proportion equation
   289,686 : 424,158.75 = 424,158.75 : x
2. Step 2: Convert to fraction form
   289,686/424,158.75 = 424,158.75/x
3. Step 3: Cross multiply
   289,686x = 424,158.75 × 424,158.75
4. Step 4: Simplify right side
   289,686x = 179,910,645,201.56
5. Step 5: Solve for x
   x = 179,910,645,201.56/289,686
6. Step 6: Final answer
   x = 621,053.99