Finding the Third Proportional to 390,991.50 and 851,967

Step by Step Solution

1. Step 1: Write the proportion equation
   390,991.50 : 851,967 = 851,967 : x
2. Step 2: Convert to fraction form
   390,991.50/851,967 = 851,967/x
3. Step 3: Cross multiply
   390,991.50x = 851,967 × 851,967
4. Step 4: Simplify right side
   390,991.50x = 725,847,769,089
5. Step 5: Solve for x
   x = 725,847,769,089/390,991.50
6. Step 6: Final answer
   x = 1,856,428.51