Finding the Third Proportional to 399,303 and 603,111

Step by Step Solution

1. Step 1: Write the proportion equation
   399,303 : 603,111 = 603,111 : x
2. Step 2: Convert to fraction form
   399,303/603,111 = 603,111/x
3. Step 3: Cross multiply
   399,303x = 603,111 × 603,111
4. Step 4: Simplify right side
   399,303x = 363,742,878,321
5. Step 5: Solve for x
   x = 363,742,878,321/399,303
6. Step 6: Final answer
   x = 910,944.52