Finding the Third Proportional to 189,405 and 315,636

Step by Step Solution

1. Step 1: Write the proportion equation
   189,405 : 315,636 = 315,636 : x
2. Step 2: Convert to fraction form
   189,405/315,636 = 315,636/x
3. Step 3: Cross multiply
   189,405x = 315,636 × 315,636
4. Step 4: Simplify right side
   189,405x = 99,626,084,496
5. Step 5: Solve for x
   x = 99,626,084,496/189,405
6. Step 6: Final answer
   x = 525,995.01