Finding the Third Proportional to 287,410.50 and 435,091.50

Step by Step Solution

1. Step 1: Write the proportion equation
   287,410.50 : 435,091.50 = 435,091.50 : x
2. Step 2: Convert to fraction form
   287,410.50/435,091.50 = 435,091.50/x
3. Step 3: Cross multiply
   287,410.50x = 435,091.50 × 435,091.50
4. Step 4: Simplify right side
   287,410.50x = 189,304,613,372.25
5. Step 5: Solve for x
   x = 189,304,613,372.25/287,410.50
6. Step 6: Final answer
   x = 658,655.87