Finding the Third Proportional to 391,980 and 831,061

Step by Step Solution

1. Step 1: Write the proportion equation
   391,980 : 831,061 = 831,061 : x
2. Step 2: Convert to fraction form
   391,980/831,061 = 831,061/x
3. Step 3: Cross multiply
   391,980x = 831,061 × 831,061
4. Step 4: Simplify right side
   391,980x = 690,662,385,721
5. Step 5: Solve for x
   x = 690,662,385,721/391,980
6. Step 6: Final answer
   x = 1,761,983.74