Finding the Third Proportional to 217,407 and 300,406.50

Step by Step Solution

1. Step 1: Write the proportion equation
   217,407 : 300,406.50 = 300,406.50 : x
2. Step 2: Convert to fraction form
   217,407/300,406.50 = 300,406.50/x
3. Step 3: Cross multiply
   217,407x = 300,406.50 × 300,406.50
4. Step 4: Simplify right side
   217,407x = 90,244,065,242.25
5. Step 5: Solve for x
   x = 90,244,065,242.25/217,407
6. Step 6: Final answer
   x = 415,092.73