Finding the Third Proportional to 256,853 and 402,912.50

Step by Step Solution

1. Step 1: Write the proportion equation
   256,853 : 402,912.50 = 402,912.50 : x
2. Step 2: Convert to fraction form
   256,853/402,912.50 = 402,912.50/x
3. Step 3: Cross multiply
   256,853x = 402,912.50 × 402,912.50
4. Step 4: Simplify right side
   256,853x = 162,338,482,656.25
5. Step 5: Solve for x
   x = 162,338,482,656.25/256,853
6. Step 6: Final answer
   x = 632,028.76