Finding the Third Proportional to 155,288 and 212,155

Step by Step Solution

1. Step 1: Write the proportion equation
   155,288 : 212,155 = 212,155 : x
2. Step 2: Convert to fraction form
   155,288/212,155 = 212,155/x
3. Step 3: Cross multiply
   155,288x = 212,155 × 212,155
4. Step 4: Simplify right side
   155,288x = 45,009,744,025
5. Step 5: Solve for x
   x = 45,009,744,025/155,288
6. Step 6: Final answer
   x = 289,846.89