Finding the Third Proportional to 31,590 and 68,240

Step by Step Solution

1. Step 1: Write the proportion equation
   31,590 : 68,240 = 68,240 : x
2. Step 2: Convert to fraction form
   31,590/68,240 = 68,240/x
3. Step 3: Cross multiply
   31,590x = 68,240 × 68,240
4. Step 4: Simplify right side
   31,590x = 4,656,697,600
5. Step 5: Solve for x
   x = 4,656,697,600/31,590
6. Step 6: Final answer
   x = 147,410.50