Finding the Third Proportional to 31,081.50 and 72,409.50

Step by Step Solution

1. Step 1: Write the proportion equation
   31,081.50 : 72,409.50 = 72,409.50 : x
2. Step 2: Convert to fraction form
   31,081.50/72,409.50 = 72,409.50/x
3. Step 3: Cross multiply
   31,081.50x = 72,409.50 × 72,409.50
4. Step 4: Simplify right side
   31,081.50x = 5,243,135,690.25
5. Step 5: Solve for x
   x = 5,243,135,690.25/31,081.50
6. Step 6: Final answer
   x = 168,689.92