Finding the Third Proportional to 31,978 and 69,992

Step by Step Solution

1. Step 1: Write the proportion equation
   31,978 : 69,992 = 69,992 : x
2. Step 2: Convert to fraction form
   31,978/69,992 = 69,992/x
3. Step 3: Cross multiply
   31,978x = 69,992 × 69,992
4. Step 4: Simplify right side
   31,978x = 4,898,880,064
5. Step 5: Solve for x
   x = 4,898,880,064/31,978
6. Step 6: Final answer
   x = 153,195.32