Finding the Third Proportional to 5,121.75 and 7,729.69

Step by Step Solution

1. Step 1: Write the proportion equation
   5,121.75 : 7,729.69 = 7,729.69 : x
2. Step 2: Convert to fraction form
   5,121.75/7,729.69 = 7,729.69/x
3. Step 3: Cross multiply
   5,121.75x = 7,729.69 × 7,729.69
4. Step 4: Simplify right side
   5,121.75x = 59,748,068.85
5. Step 5: Solve for x
   x = 59,748,068.85/5,121.75
6. Step 6: Final answer
   x = 11,665.56