Finding the Third Proportional to 30,978 and 68,402

Step by Step Solution

1. Step 1: Write the proportion equation
   30,978 : 68,402 = 68,402 : x
2. Step 2: Convert to fraction form
   30,978/68,402 = 68,402/x
3. Step 3: Cross multiply
   30,978x = 68,402 × 68,402
4. Step 4: Simplify right side
   30,978x = 4,678,833,604
5. Step 5: Solve for x
   x = 4,678,833,604/30,978
6. Step 6: Final answer
   x = 151,037.30