Finding the Third Proportional to 144,256.50 and 315,081

Step by Step Solution

1. Step 1: Write the proportion equation
   144,256.50 : 315,081 = 315,081 : x
2. Step 2: Convert to fraction form
   144,256.50/315,081 = 315,081/x
3. Step 3: Cross multiply
   144,256.50x = 315,081 × 315,081
4. Step 4: Simplify right side
   144,256.50x = 99,276,036,561
5. Step 5: Solve for x
   x = 99,276,036,561/144,256.50
6. Step 6: Final answer
   x = 688,191.08