Finding the Third Proportional to 391,980 and 831,060

Step by Step Solution

1. Step 1: Write the proportion equation
   391,980 : 831,060 = 831,060 : x
2. Step 2: Convert to fraction form
   391,980/831,060 = 831,060/x
3. Step 3: Cross multiply
   391,980x = 831,060 × 831,060
4. Step 4: Simplify right side
   391,980x = 690,660,723,600
5. Step 5: Solve for x
   x = 690,660,723,600/391,980
6. Step 6: Final answer
   x = 1,761,979.50