Finding the Third Proportional to 85,420.50 and 186,931.50

Step by Step Solution

1. Step 1: Write the proportion equation
   85,420.50 : 186,931.50 = 186,931.50 : x
2. Step 2: Convert to fraction form
   85,420.50/186,931.50 = 186,931.50/x
3. Step 3: Cross multiply
   85,420.50x = 186,931.50 × 186,931.50
4. Step 4: Simplify right side
   85,420.50x = 34,943,385,692.25
5. Step 5: Solve for x
   x = 34,943,385,692.25/85,420.50
6. Step 6: Final answer
   x = 409,074.94