Finding the Third Proportional to 133,015.50 and 287,131.50

Step by Step Solution

1. Step 1: Write the proportion equation
   133,015.50 : 287,131.50 = 287,131.50 : x
2. Step 2: Convert to fraction form
   133,015.50/287,131.50 = 287,131.50/x
3. Step 3: Cross multiply
   133,015.50x = 287,131.50 × 287,131.50
4. Step 4: Simplify right side
   133,015.50x = 82,444,498,292.25
5. Step 5: Solve for x
   x = 82,444,498,292.25/133,015.50
6. Step 6: Final answer
   x = 619,811.21