Finding the Third Proportional to 681,979.50 and 813,199.50

Step by Step Solution

1. Step 1: Write the proportion equation
   681,979.50 : 813,199.50 = 813,199.50 : x
2. Step 2: Convert to fraction form
   681,979.50/813,199.50 = 813,199.50/x
3. Step 3: Cross multiply
   681,979.50x = 813,199.50 × 813,199.50
4. Step 4: Simplify right side
   681,979.50x = 661,293,426,800.25
5. Step 5: Solve for x
   x = 661,293,426,800.25/681,979.50
6. Step 6: Final answer
   x = 969,667.60