Finding the Third Proportional to 209,154 and 315,697.50

Step by Step Solution

1. Step 1: Write the proportion equation
   209,154 : 315,697.50 = 315,697.50 : x
2. Step 2: Convert to fraction form
   209,154/315,697.50 = 315,697.50/x
3. Step 3: Cross multiply
   209,154x = 315,697.50 × 315,697.50
4. Step 4: Simplify right side
   209,154x = 99,664,911,506.25
5. Step 5: Solve for x
   x = 99,664,911,506.25/209,154
6. Step 6: Final answer
   x = 476,514.49