Finding the Third Proportional to 118,309.78 and 256,581.42

Step by Step Solution

1. Step 1: Write the proportion equation
   118,309.78 : 256,581.42 = 256,581.42 : x
2. Step 2: Convert to fraction form
   118,309.78/256,581.42 = 256,581.42/x
3. Step 3: Cross multiply
   118,309.78x = 256,581.42 × 256,581.42
4. Step 4: Simplify right side
   118,309.78x = 65,834,026,051.40
5. Step 5: Solve for x
   x = 65,834,026,051.40/118,309.78
6. Step 6: Final answer
   x = 556,454.63