Finding the Third Proportional to 31,780 and 68,146

Step by Step Solution

1. Step 1: Write the proportion equation
   31,780 : 68,146 = 68,146 : x
2. Step 2: Convert to fraction form
   31,780/68,146 = 68,146/x
3. Step 3: Cross multiply
   31,780x = 68,146 × 68,146
4. Step 4: Simplify right side
   31,780x = 4,643,877,316
5. Step 5: Solve for x
   x = 4,643,877,316/31,780
6. Step 6: Final answer
   x = 146,125.78