Finding the Third Proportional to 139,459 and 286,268.75

Step by Step Solution

1. Step 1: Write the proportion equation
   139,459 : 286,268.75 = 286,268.75 : x
2. Step 2: Convert to fraction form
   139,459/286,268.75 = 286,268.75/x
3. Step 3: Cross multiply
   139,459x = 286,268.75 × 286,268.75
4. Step 4: Simplify right side
   139,459x = 81,949,797,226.56
5. Step 5: Solve for x
   x = 81,949,797,226.56/139,459
6. Step 6: Final answer
   x = 587,626.45