Finding the Third Proportional to 211,599 and 287,053.50

Step by Step Solution

1. Step 1: Write the proportion equation
   211,599 : 287,053.50 = 287,053.50 : x
2. Step 2: Convert to fraction form
   211,599/287,053.50 = 287,053.50/x
3. Step 3: Cross multiply
   211,599x = 287,053.50 × 287,053.50
4. Step 4: Simplify right side
   211,599x = 82,399,711,862.25
5. Step 5: Solve for x
   x = 82,399,711,862.25/211,599
6. Step 6: Final answer
   x = 389,414.47