Finding the Third Proportional to 5,166 and 7,780.50

Step by Step Solution

1. Step 1: Write the proportion equation
   5,166 : 7,780.50 = 7,780.50 : x
2. Step 2: Convert to fraction form
   5,166/7,780.50 = 7,780.50/x
3. Step 3: Cross multiply
   5,166x = 7,780.50 × 7,780.50
4. Step 4: Simplify right side
   5,166x = 60,536,180.25
5. Step 5: Solve for x
   x = 60,536,180.25/5,166
6. Step 6: Final answer
   x = 11,718.19