Finding the Third Proportional to 287,980.50 and 405,361.50

Step by Step Solution

1. Step 1: Write the proportion equation
   287,980.50 : 405,361.50 = 405,361.50 : x
2. Step 2: Convert to fraction form
   287,980.50/405,361.50 = 405,361.50/x
3. Step 3: Cross multiply
   287,980.50x = 405,361.50 × 405,361.50
4. Step 4: Simplify right side
   287,980.50x = 164,317,945,682.25
5. Step 5: Solve for x
   x = 164,317,945,682.25/287,980.50
6. Step 6: Final answer
   x = 570,587.06