Finding the Third Proportional to 218 and 429.50

Step by Step Solution

1. Step 1: Write the proportion equation
   218 : 429.50 = 429.50 : x
2. Step 2: Convert to fraction form
   218/429.50 = 429.50/x
3. Step 3: Cross multiply
   218x = 429.50 × 429.50
4. Step 4: Simplify right side
   218x = 184,470.25
5. Step 5: Solve for x
   x = 184,470.25/218
6. Step 6: Final answer
   x = 846.19