Finding the Third Proportional to 15,688.69 and 21,163.78

Step by Step Solution

1. Step 1: Write the proportion equation
   15,688.69 : 21,163.78 = 21,163.78 : x
2. Step 2: Convert to fraction form
   15,688.69/21,163.78 = 21,163.78/x
3. Step 3: Cross multiply
   15,688.69x = 21,163.78 × 21,163.78
4. Step 4: Simplify right side
   15,688.69x = 447,905,636.80
5. Step 5: Solve for x
   x = 447,905,636.80/15,688.69
6. Step 6: Final answer
   x = 28,549.59