Finding the Third Proportional to 64,400 and 140,242

Step by Step Solution

1. Step 1: Write the proportion equation
   64,400 : 140,242 = 140,242 : x
2. Step 2: Convert to fraction form
   64,400/140,242 = 140,242/x
3. Step 3: Cross multiply
   64,400x = 140,242 × 140,242
4. Step 4: Simplify right side
   64,400x = 19,667,818,564
5. Step 5: Solve for x
   x = 19,667,818,564/64,400
6. Step 6: Final answer
   x = 305,400.91