Finding the Third Proportional to 505,160 and 780,256

Step by Step Solution

1. Step 1: Write the proportion equation
   505,160 : 780,256 = 780,256 : x
2. Step 2: Convert to fraction form
   505,160/780,256 = 780,256/x
3. Step 3: Cross multiply
   505,160x = 780,256 × 780,256
4. Step 4: Simplify right side
   505,160x = 608,799,425,536
5. Step 5: Solve for x
   x = 608,799,425,536/505,160
6. Step 6: Final answer
   x = 1,205,161.58