Finding the Third Proportional to 105,591.75 and 212,911.50

Step by Step Solution

1. Step 1: Write the proportion equation
   105,591.75 : 212,911.50 = 212,911.50 : x
2. Step 2: Convert to fraction form
   105,591.75/212,911.50 = 212,911.50/x
3. Step 3: Cross multiply
   105,591.75x = 212,911.50 × 212,911.50
4. Step 4: Simplify right side
   105,591.75x = 45,331,306,832.25
5. Step 5: Solve for x
   x = 45,331,306,832.25/105,591.75
6. Step 6: Final answer
   x = 429,307.28