Finding the Third Proportional to 249,886.50 and 356,139

Step by Step Solution

1. Step 1: Write the proportion equation
   249,886.50 : 356,139 = 356,139 : x
2. Step 2: Convert to fraction form
   249,886.50/356,139 = 356,139/x
3. Step 3: Cross multiply
   249,886.50x = 356,139 × 356,139
4. Step 4: Simplify right side
   249,886.50x = 126,834,987,321
5. Step 5: Solve for x
   x = 126,834,987,321/249,886.50
6. Step 6: Final answer
   x = 507,570.39